Merge pull request #2284 from akohlmey/fix-tester

Add unit test tool for fixes that do time integration, thermostatting, force manipulations and similar
2020-08-13 10:23:29 -04:00 · 2020-08-13 10:23:29 -04:00 · 1c2747739a
parent ac43f8f685 adf8d638e8
commit 1c2747739a
70 changed files with 4066 additions and 75 deletions
--- a/cmake/Modules/Documentation.cmake
+++ b/cmake/Modules/Documentation.cmake
@ -29,8 +29,8 @@ if(BUILD_DOC)
    OUTPUT requirements.txt
    DEPENDS docenv
    COMMAND ${CMAKE_COMMAND} -E copy ${LAMMPS_DOC_DIR}/utils/requirements.txt requirements.txt
-    COMMAND ${DOCENV_BINARY_DIR}/pip install -r requirements.txt --upgrade
    COMMAND ${DOCENV_BINARY_DIR}/pip install --upgrade ${LAMMPS_DOC_DIR}/utils/converters
+    COMMAND ${DOCENV_BINARY_DIR}/pip install --use-feature=2020-resolver -r requirements.txt --upgrade
  )

  # download mathjax distribution and unpack to folder "mathjax"
--- a/doc/Makefile
+++ b/doc/Makefile
@ -194,7 +194,7 @@ $(VENV):
 		$(VIRTUALENV) -p $(PYTHON) $(VENV); \
 		. $(VENV)/bin/activate; \
 		pip install --upgrade pip; \
-		pip install -r requirements.txt; \
+		pip install --use-feature=2020-resolver -r requirements.txt; \
 		deactivate;\
 	)

--- a/doc/src/Build_development.rst
+++ b/doc/src/Build_development.rst
@ -159,8 +159,8 @@ A test run is then a a collection multiple individual test runs each
 with many comparisons to reference results based on template input
 files, individual command settings, relative error margins, and
 reference data stored in a YAML format file with ``.yaml``
-suffix. Currently the programs ``pair_style``, ``bond_style``, and
-``angle_style`` are implemented.  They will compare forces, energies and
+suffix. Currently the programs ``test_pair_style``, ``test_bond_style``, and
+``test_angle_style`` are implemented.  They will compare forces, energies and
 (global) stress for all atoms after a ``run 0`` calculation and after a
 few steps of MD with :doc:`fix nve <fix_nve>`, each in multiple variants
 with different settings and also for multiple accelerated styles. If a
@ -172,7 +172,7 @@ Below is an example command and output:

 .. parsed-literal::

-   [tests]$ pair_style mol-pair-lj_cut.yaml
+   [tests]$ test_pair_style mol-pair-lj_cut.yaml
   [==========] Running 6 tests from 1 test suite.
   [----------] Global test environment set-up.
   [----------] 6 tests from PairStyle
@ -259,13 +259,61 @@ and working.
     of mis-compiled code (or an undesired large loss of precision due
     to significant reordering of operations and thus less error cancellation).

+Unit tests for timestepping related fixes
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+A substantial subset of :doc:`fix styles <fix>` are invoked regularly
+during MD timestepping and manipulate per-atom properties like
+positions, velocities, and forces.  For those fix styles, testing can be
+done in a very similar fashion as for force fields and thus there is a
+test program `test_fix_timestep` that shares a lot of code, properties,
+and command line flags with the force field style testers described in
+the previous section.
+
+This tester will set up a small molecular system run with verlet run
+style for 4 MD steps, then write a binary restart and continue for
+another 4 MD steps. At this point coordinates and velocities are
+recorded and compared to reference data. Then the system is cleared,
+restarted and running the second 4 MD steps again and the data is
+compared to the same reference. That is followed by another restart
+after which per atom type masses are replaced with per-atom masses and
+the second 4 MD steps are repeated again and compared to the same
+reference.  Also global scalar and vector data of the fix is recorded
+and compared.  If the fix is a thermostat and thus the internal property
+``t_target`` can be extracted, then this is compared to the reference
+data.  The tests are repeated with the respa run style.
+
+If the fix has a multi-threaded version in the USER-OMP package, then
+the entire set of tests is repeated for that version as well.
+
+For this to work, some additional conditions have to be met by the
+YAML format test inputs.
+
+- The fix to be tested (and only this fix), should be listed in the
+  ``prerequisites:`` section
+- The fix to be tested must be specified in the ``post_commands:``
+  section with the fix-ID ``test``.  This section may contain other
+  commands and other fixes (e.g. an instance of fix nve for testing
+  a thermostat or force manipulation fix)
+- For fixes that can tally contributions to the global virial, the
+  line ``fix_modify test virial yes`` should be included in the
+  ``post_commands:`` section of the test input.
+- For thermostat fixes the target temperature should be ramped from
+  an arbitrary value (e.g. 50K) to a pre-defined target temperature
+  entered as ``${t_target}``.
+- For fixes that have thermostatting support included, but do not
+  have it enabled in the input (e.g. fix rigid with default settings),
+  the ``post_commands:`` section should contain the line
+  ``variable t_target delete`` to disable the target temperature ramp
+  check to avoid false positives.
+
 Use custom linker for faster link times when ENABLE_TESTING is active
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

 When compiling LAMMPS with enabled tests, most test executables will
-need to be linked against the LAMMPS library.  Since this can be a
-large with many C++ objects when many packages are enabled, link times
-can become very long on machines that use the GNU BFD linker (e.g.
+need to be linked against the LAMMPS library.  Since this can be a very
+large library with many C++ objects when many packages are enabled, link
+times can become very long on machines that use the GNU BFD linker (e.g.
 Linux systems).  Alternatives like the ``lld`` linker of the LLVM project
 or the ``gold`` linker available with GNU binutils can speed up this step
 substantially. CMake will by default test if any of the two can be
--- a/doc/src/fix_temp_berendsen.rst
+++ b/doc/src/fix_temp_berendsen.rst
@ -119,7 +119,11 @@ thermal degrees of freedom, and the bias is added back in.

 **Restart, fix_modify, output, run start/stop, minimize info:**

-No information about this fix is written to :doc:`binary restart files <restart>`.
+This fix writes the cumulative global energy change to
+:doc:`binary restart files <restart>`.  See the
+:doc:`read_restart <read_restart>` command for info on how to
+re-specify a fix in an input script that reads a restart file,
+so that the fix continues in an uninterrupted fashion.

 The :doc:`fix_modify <fix_modify>` *temp* option is supported by this
 fix.  You can use it to assign a temperature :doc:`compute <compute>`
--- a/doc/src/fix_temp_csvr.rst
+++ b/doc/src/fix_temp_csvr.rst
@ -127,6 +127,14 @@ thermal degrees of freedom, and the bias is added back in.

 **Restart, fix_modify, output, run start/stop, minimize info:**

+These fixes write the cumulative global energy change and the
+random number generator states to :doc:`binary restart files <restart>`.
+See the :doc:`read_restart <read_restart>` command for info on how to
+re-specify a fix in an input script that reads a restart file,
+so that the selected fix continues in an uninterrupted fashion.  The
+random number generator state can only be restored when the number
+of processors remains unchanged from what is recorded in the restart file.
+
 No information about these fixes are written to :doc:`binary restart files <restart>`.

 The :doc:`fix_modify <fix_modify>` *temp* option is supported by these
--- a/doc/src/pair_table.rst
+++ b/doc/src/pair_table.rst
@ -60,7 +60,7 @@ For the *linear* style, the distance *R* is used to find the 2
 surrounding table values from which an energy or force is computed by
 linear interpolation.

-For the *spline* style, a cubic spline coefficients are computed and
+For the *spline* style, cubic spline coefficients are computed and
 stored for each of the *N* values in the table, one set of splines for
 energy, another for force.  Note that these splines are different than
 the ones used to pre-compute the *N* values.  Those splines were fit
--- a/src/KSPACE/pair_lj_cut_coul_long.cpp
+++ b/src/KSPACE/pair_lj_cut_coul_long.cpp
@ -545,10 +545,7 @@ void PairLJCutCoulLong::compute_outer(int eflag, int vflag)
            }
          } else forcecoul = 0.0;

-          if (rsq <= cut_in_off_sq) {
-            r6inv = r2inv*r2inv*r2inv;
-            forcelj = r6inv * (lj1[itype][jtype]*r6inv - lj2[itype][jtype]);
-          } else if (rsq <= cut_in_on_sq) {
+          if (rsq < cut_ljsq[itype][jtype]) {
            r6inv = r2inv*r2inv*r2inv;
            forcelj = r6inv * (lj1[itype][jtype]*r6inv - lj2[itype][jtype]);
          }
--- a/src/USER-MISC/pair_e3b.cpp
+++ b/src/USER-MISC/pair_e3b.cpp
@ -382,8 +382,6 @@ void PairE3B::settings(int narg, char **arg)
 {
  if (narg != 1) error->all(FLERR,"Illegal pair_style command");
  typeO=force->inumeric(FLERR,arg[0]);
-  if (typeO<1 || typeO>atom->ntypes)
-    error->all(FLERR,"Invalid Otype: out of bounds");
 }

 /* ----------------------------------------------------------------------
@ -477,6 +475,8 @@ void PairE3B::init_style()
    error->all(FLERR,"Pair style E3B requires atom IDs");
  if (force->newton_pair == 0)
    error->all(FLERR,"Pair style E3B requires newton pair on");
+  if (typeO<1 || typeO>atom->ntypes)
+    error->all(FLERR,"Invalid Otype: out of bounds");

  // need a half neighbor list
  neighbor->request(this,instance_me);
--- a/src/USER-MISC/pair_edip.cpp
+++ b/src/USER-MISC/pair_edip.cpp
@ -51,7 +51,13 @@ using namespace LAMMPS_NS;

 /* ---------------------------------------------------------------------- */

-PairEDIP::PairEDIP(LAMMPS *lmp) : Pair(lmp)
+PairEDIP::PairEDIP(LAMMPS *lmp) :
+  Pair(lmp), preInvR_ij(NULL), preExp3B_ij(NULL), preExp3BDerived_ij(NULL),
+  preExp2B_ij(NULL), preExp2BDerived_ij(NULL), prePow2B_ij(NULL),
+  preForceCoord(NULL), cutoffFunction(NULL), cutoffFunctionDerived(NULL),
+  pow2B(NULL), exp2B(NULL), exp3B(NULL),  qFunctionGrid(NULL),
+  expMinusBetaZeta_iZeta_iGrid(NULL), tauFunctionGrid(NULL),
+  tauFunctionDerivedGrid(NULL)
 {
  single_enable = 0;
  restartinfo = 0;
@ -503,6 +509,8 @@ void PairEDIP::allocateGrids(void)
  double maxArgumentExpMinusBetaZeta_iZeta_i;
  double const leftLimitToZero = -DBL_MIN * 1000.0;

+  deallocateGrids();
+
  // tauFunctionGrid

  maxArgumentTauFunctionGrid = leadDimInteractionList;
@ -561,6 +569,7 @@ void PairEDIP::allocatePreLoops(void)
 {
  int nthreads = comm->nthreads;

+  deallocatePreLoops();
  memory->create(preInvR_ij,nthreads*leadDimInteractionList,"edip:preInvR_ij");
  memory->create(preExp3B_ij,nthreads*leadDimInteractionList,"edip:preExp3B_ij");
  memory->create(preExp3BDerived_ij,nthreads*leadDimInteractionList,
--- a/src/USER-MISC/pair_lennard_mdf.cpp
+++ b/src/USER-MISC/pair_lennard_mdf.cpp
@ -226,8 +226,8 @@ void PairLennardMDF::coeff(int narg, char **arg)
    cut_inner_one = force->numeric(FLERR,arg[4]);
    cut_one = force->numeric(FLERR,arg[5]);
  }
-  if (cut_inner_global <= 0.0 || cut_inner_global > cut_global)
-    error->all(FLERR,"Illegal pair_style command");
+  if (cut_inner_one <= 0.0 || cut_inner_one > cut_one)
+    error->all(FLERR,"Illegal pair_coeff command");

  int count = 0;
  for (int i = ilo; i <= ihi; i++) {
@ -328,6 +328,8 @@ void PairLennardMDF::read_restart(FILE *fp)
 void PairLennardMDF::write_restart_settings(FILE *fp)
 {
  fwrite(&mix_flag,sizeof(int),1,fp);
+  fwrite(&cut_global,sizeof(double),1,fp);
+  fwrite(&cut_inner_global,sizeof(double),1,fp);
 }

 /* ----------------------------------------------------------------------
@ -339,8 +341,12 @@ void PairLennardMDF::read_restart_settings(FILE *fp)
  int me = comm->me;
  if (me == 0) {
    utils::sfread(FLERR,&mix_flag,sizeof(int),1,fp,NULL,error);
+    utils::sfread(FLERR,&cut_global,sizeof(double),1,fp,NULL,error);
+    utils::sfread(FLERR,&cut_inner_global,sizeof(double),1,fp,NULL,error);
  }
  MPI_Bcast(&mix_flag,1,MPI_INT,0,world);
+  MPI_Bcast(&cut_global,1,MPI_DOUBLE,0,world);
+  MPI_Bcast(&cut_inner_global,1,MPI_DOUBLE,0,world);
 }

 /* ----------------------------------------------------------------------
--- a/src/USER-MISC/pair_lj_expand_coul_long.cpp
+++ b/src/USER-MISC/pair_lj_expand_coul_long.cpp
@ -53,6 +53,7 @@ PairLJExpandCoulLong::PairLJExpandCoulLong(LAMMPS *lmp) : Pair(lmp)
  writedata = 1;
  ftable = NULL;
  qdist = 0.0;
+  cut_respa = NULL;
 }

 /* ---------------------------------------------------------------------- */
@ -167,7 +168,7 @@ void PairLJExpandCoulLong::compute(int eflag, int vflag)
          rshift2inv = 1.0/rshiftsq;
          r6inv = rshift2inv*rshift2inv*rshift2inv;
          forcelj = r6inv * (lj1[itype][jtype]*r6inv - lj2[itype][jtype]);
-          forcelj = factor_lj*forcelj/rshift/r;
+          forcelj *= factor_lj/rshift/r;
        } else forcelj = 0.0;

        fpair = forcecoul*r2inv + forcelj;
@ -276,7 +277,7 @@ void PairLJExpandCoulLong::compute_inner()
          rshift2inv = 1.0/rshiftsq;
          r6inv = rshift2inv*rshift2inv*rshift2inv;
          forcelj = r6inv * (lj1[itype][jtype]*r6inv - lj2[itype][jtype]);
-          forcelj = factor_lj*forcelj/rshift/r;
+          forcelj *= factor_lj/rshift/r;
        } else forcelj = 0.0;

        fpair = forcecoul*r2inv + forcelj;
@ -371,7 +372,7 @@ void PairLJExpandCoulLong::compute_middle()
          rshift2inv = 1.0/rshiftsq;
          r6inv = rshift2inv*rshift2inv*rshift2inv;
          forcelj = r6inv * (lj1[itype][jtype]*r6inv - lj2[itype][jtype]);
-          forcelj = factor_lj*forcelj/rshift/r;
+          forcelj *= factor_lj/rshift/r;
        } else forcelj = 0.0;

        fpair = forcecoul*r2inv + forcelj;
@ -506,7 +507,7 @@ void PairLJExpandCoulLong::compute_outer(int eflag, int vflag)
          rshift2inv = 1.0/rshiftsq;
          r6inv = rshift2inv*rshift2inv*rshift2inv;
          forcelj = r6inv * (lj1[itype][jtype]*r6inv - lj2[itype][jtype]);
-          forcelj = factor_lj*forcelj/rshift/r;
+          forcelj *= factor_lj/rshift/r;
          if (rsq < cut_in_on_sq) {
            rsw = (sqrt(rsq) - cut_in_off)/cut_in_diff;
            forcelj *= rsw*rsw*(3.0 - 2.0*rsw);
@ -524,6 +525,7 @@ void PairLJExpandCoulLong::compute_outer(int eflag, int vflag)
          f[j][2] -= delz*fpair;
        }

+        if (evflag) ecoul = evdwl = 0.0;
        if (eflag) {
          if (rsq < cut_coulsq) {
            if (!ncoultablebits || rsq <= tabinnersq) {
@ -538,14 +540,18 @@ void PairLJExpandCoulLong::compute_outer(int eflag, int vflag)
                ecoul -= (1.0-factor_coul)*prefactor;
              }
            }
-          } else ecoul = 0.0;
+          }

          if (rsq < cut_ljsq[itype][jtype]) {
-            r6inv = r2inv*r2inv*r2inv;
+            r = sqrt(rsq);
+            rshift = r - shift[itype][jtype];
+            rshiftsq = rshift*rshift;
+            rshift2inv = 1.0/rshiftsq;
+            r6inv = rshift2inv*rshift2inv*rshift2inv;
            evdwl = r6inv*(lj3[itype][jtype]*r6inv-lj4[itype][jtype]) -
              offset[itype][jtype];
            evdwl *= factor_lj;
-          } else evdwl = 0.0;
+          }
        }

        if (vflag) {
@ -564,15 +570,18 @@ void PairLJExpandCoulLong::compute_outer(int eflag, int vflag)
            }
          } else forcecoul = 0.0;

-          if (rsq <= cut_in_off_sq) {
-            r6inv = r2inv*r2inv*r2inv;
+          if (rsq < cut_ljsq[itype][jtype]) {
+            r = sqrt(rsq);
+            rshift = r - shift[itype][jtype];
+            rshiftsq = rshift*rshift;
+            rshift2inv = 1.0/rshiftsq;
+            r6inv = rshift2inv*rshift2inv*rshift2inv;
            forcelj = r6inv * (lj1[itype][jtype]*r6inv - lj2[itype][jtype]);
-          } else if (rsq <= cut_in_on_sq) {
-            r6inv = r2inv*r2inv*r2inv;
-            forcelj = r6inv * (lj1[itype][jtype]*r6inv - lj2[itype][jtype]);
-          }
-          fpair = (forcecoul + factor_lj*forcelj) * r2inv;
-        }
+            forcelj *= factor_lj/rshift/r;
+          } else forcelj = 0.0;
+
+          fpair = forcecoul*r2inv + forcelj;
+        } else fpair = 0.0;

        if (evflag) ev_tally(i,j,nlocal,newton_pair,
                             evdwl,ecoul,fpair,delx,dely,delz);
@ -946,11 +955,16 @@ double PairLJExpandCoulLong::single(int i, int j, int itype, int jtype,
  } else forcecoul = 0.0;

  if (rsq < cut_ljsq[itype][jtype]) {
-    r6inv = r2inv*r2inv*r2inv;
+    r = sqrt(rsq);
+    double rshift = r - shift[itype][jtype];
+    double rshiftsq = rshift*rshift;
+    double rshift2inv = 1.0/rshiftsq;
+    r6inv = rshift2inv*rshift2inv*rshift2inv;
    forcelj = r6inv * (lj1[itype][jtype]*r6inv - lj2[itype][jtype]);
+    forcelj *= factor_lj/rshift/r;
  } else forcelj = 0.0;

-  fforce = (forcecoul + factor_lj*forcelj) * r2inv;
+  fforce = forcecoul*r2inv + forcelj;

  double eng = 0.0;
  if (rsq < cut_coulsq) {
--- a/src/USER-MISC/pair_meam_spline.cpp
+++ b/src/USER-MISC/pair_meam_spline.cpp
@ -57,6 +57,7 @@ PairMEAMSpline::PairMEAMSpline(LAMMPS *lmp) : Pair(lmp)

  nelements = 0;
  elements = NULL;
+  map = NULL;

  Uprime_values = NULL;
  nmax = 0;
@ -65,6 +66,14 @@ PairMEAMSpline::PairMEAMSpline(LAMMPS *lmp) : Pair(lmp)

  comm_forward = 1;
  comm_reverse = 0;
+
+  phis = NULL;
+  Us = NULL;
+  rhos = NULL;
+  fs = NULL;
+  gs = NULL;
+
+  zero_atom_energies = NULL;
 }

 /* ---------------------------------------------------------------------- */
@ -332,6 +341,8 @@ void PairMEAMSpline::allocate()
  allocated = 1;
  int n = nelements;

+  memory->destroy(setflag);
+  memory->destroy(cutsq);
  memory->create(setflag,n+1,n+1,"pair:setflag");
  memory->create(cutsq,n+1,n+1,"pair:cutsq");

@ -339,14 +350,21 @@ void PairMEAMSpline::allocate()
  //Change the functional form
  //f_ij->f_i
  //g_i(cos\theta_ijk)->g_jk(cos\theta_ijk)
+  delete[] phis;
+  delete[] Us;
+  delete[] rhos;
+  delete[] fs;
+  delete[] gs;
  phis = new SplineFunction[nmultichoose2];
  Us = new SplineFunction[n];
  rhos = new SplineFunction[n];
  fs = new SplineFunction[n];
  gs = new SplineFunction[nmultichoose2];

+  delete[] zero_atom_energies;
  zero_atom_energies = new double[n];

+  delete[] map;
  map = new int[n+1];
  for (int i=0; i <= n; ++i) map[i] = -1;
 }
@ -470,6 +488,9 @@ void PairMEAMSpline::read_file(const char* filename)
      if (nelements < 1)
        error->one(FLERR, "Invalid number of atomic species on"
                   " meam/spline line in potential file");
+      if (elements)
+        for (int i = 0; i < nelements; i++) delete [] elements[i];
+      delete [] elements;
      elements = new char*[nelements];
      for (int i=0; i<nelements; ++i) {
        ptr = strtok(NULL," \t\n\r\f");
--- a/src/USER-MISC/pair_morse_smooth_linear.cpp
+++ b/src/USER-MISC/pair_morse_smooth_linear.cpp
@ -201,14 +201,6 @@ void PairMorseSmoothLinear::coeff(int narg, char **arg)
      alpha[i][j] = alpha_one;
      r0[i][j] = r0_one;
      cut[i][j] = cut_one;
-
-      morse1[i][j] = 2.0*d0[i][j]*alpha[i][j];
-
-      double alpha_dr = -alpha[i][j] * (cut[i][j] - r0[i][j]);
-
-      offset[i][j]        = d0[i][j] * (exp(2.0*alpha_dr) - 2.0*exp(alpha_dr));
-      der_at_cutoff[i][j] = -2.0*alpha[i][j]*d0[i][j] * (exp(2.0*alpha_dr) - exp(alpha_dr));
-
      setflag[i][j] = 1;
      count++;
    }
@ -227,6 +219,9 @@ double PairMorseSmoothLinear::init_one(int i, int j)
  if (setflag[i][j] == 0) error->all(FLERR,"All pair coeffs are not set");

  morse1[i][j] = 2.0*d0[i][j]*alpha[i][j];
+  double alpha_dr = -alpha[i][j] * (cut[i][j] - r0[i][j]);
+  offset[i][j]        = d0[i][j] * (exp(2.0*alpha_dr) - 2.0*exp(alpha_dr));
+  der_at_cutoff[i][j] = -2.0*alpha[i][j]*d0[i][j] * (exp(2.0*alpha_dr) - exp(alpha_dr));

  d0[j][i] = d0[i][j];
  alpha[j][i] = alpha[i][j];
--- a/src/USER-OMP/pair_morse_smooth_linear_omp.cpp
+++ b/src/USER-OMP/pair_morse_smooth_linear_omp.cpp
@ -35,8 +35,6 @@ PairMorseSmoothLinearOMP::PairMorseSmoothLinearOMP(LAMMPS *lmp) :
  respa_enable = 0;
 }

-
-
 /* ---------------------------------------------------------------------- */

 void PairMorseSmoothLinearOMP::compute(int eflag, int vflag)
@ -76,8 +74,6 @@ void PairMorseSmoothLinearOMP::compute(int eflag, int vflag)
  } // end of omp parallel region
 }

-
-
 template <int EVFLAG, int EFLAG, int NEWTON_PAIR>
 void PairMorseSmoothLinearOMP::eval(int iifrom, int iito, ThrData * const thr)
 {
@ -129,7 +125,7 @@ void PairMorseSmoothLinearOMP::eval(int iifrom, int iito, ThrData * const thr)
        dexp = exp(-alpha[itype][jtype] * dr);

        fpartial = morse1[itype][jtype] * (dexp*dexp - dexp) / r;
-        fpair = factor_lj * ( fpartial - der_at_cutoff[itype][jtype] / r);
+        fpair = factor_lj * ( fpartial + der_at_cutoff[itype][jtype] / r);

        fxtmp += delx*fpair;
        fytmp += dely*fpair;
@ -143,7 +139,7 @@ void PairMorseSmoothLinearOMP::eval(int iifrom, int iito, ThrData * const thr)
        if (EFLAG) {
          evdwl = d0[itype][jtype] * (dexp*dexp - 2.0*dexp) -
                  offset[itype][jtype];
-          evdwl += ( r - cut[itype][jtype] ) * der_at_cutoff[itype][jtype];
+          evdwl -= ( r - cut[itype][jtype] ) * der_at_cutoff[itype][jtype];
          evdwl *= factor_lj;
        }

--- a/src/fix_setforce.cpp
+++ b/src/fix_setforce.cpp
@ -297,8 +297,14 @@ void FixSetForce::post_force_respa(int vflag, int ilevel, int /*iloop*/)
 {
  // set force to desired value on requested level, 0.0 on other levels

-  if (ilevel == ilevel_respa) post_force(vflag);
-  else {
+  if (ilevel == 0) foriginal_saved[0] = foriginal_saved[1] = foriginal_saved[2] = 0.0;
+
+  if (ilevel == ilevel_respa) {
+    post_force(vflag);
+    foriginal[0] += foriginal_saved[0];
+    foriginal[1] += foriginal_saved[1];
+    foriginal[2] += foriginal_saved[2];
+  } else {
    Region *region = NULL;
    if (iregion >= 0) {
      region = domain->regions[iregion];
@ -313,6 +319,9 @@ void FixSetForce::post_force_respa(int vflag, int ilevel, int /*iloop*/)
    for (int i = 0; i < nlocal; i++)
      if (mask[i] & groupbit) {
        if (region && !region->match(x[i][0],x[i][1],x[i][2])) continue;
+        foriginal_saved[0] += f[i][0];
+        foriginal_saved[1] += f[i][1];
+        foriginal_saved[2] += f[i][2];
        if (xstyle) f[i][0] = 0.0;
        if (ystyle) f[i][1] = 0.0;
        if (zstyle) f[i][2] = 0.0;
--- a/src/fix_setforce.h
+++ b/src/fix_setforce.h
@ -45,7 +45,7 @@ class FixSetForce : public Fix {
  char *xstr,*ystr,*zstr;
  char *idregion;
  int xvar,yvar,zvar,xstyle,ystyle,zstyle;
-  double foriginal[3],foriginal_all[3];
+  double foriginal[3],foriginal_all[3],foriginal_saved[3];
  int force_flag;
  int nlevels_respa,ilevel_respa;

--- a/src/fix_temp_berendsen.cpp
+++ b/src/fix_temp_berendsen.cpp
@ -43,6 +43,7 @@ FixTempBerendsen::FixTempBerendsen(LAMMPS *lmp, int narg, char **arg) :

  // Berendsen thermostat should be applied every step

+  restart_global = 1;
  dynamic_group_allow = 1;
  nevery = 1;
  scalar_flag = 1;
@ -241,6 +242,34 @@ double FixTempBerendsen::compute_scalar()
  return energy;
 }

+/* ----------------------------------------------------------------------
+   pack entire state of Fix into one write
+------------------------------------------------------------------------- */
+
+void FixTempBerendsen::write_restart(FILE *fp)
+{
+  int n = 0;
+  double list[1];
+  list[n++] = energy;
+
+  if (comm->me == 0) {
+    int size = n * sizeof(double);
+    fwrite(&size,sizeof(int),1,fp);
+    fwrite(list,sizeof(double),n,fp);
+  }
+}
+
+/* ----------------------------------------------------------------------
+   use state info from restart file to restart the Fix
+------------------------------------------------------------------------- */
+
+void FixTempBerendsen::restart(char *buf)
+{
+  double *list = (double *) buf;
+
+  energy = list[0];
+}
+
 /* ----------------------------------------------------------------------
   extract thermostat properties
 ------------------------------------------------------------------------- */
--- a/src/fix_temp_berendsen.h
+++ b/src/fix_temp_berendsen.h
@ -34,6 +34,8 @@ class FixTempBerendsen : public Fix {
  int modify_param(int, char **);
  void reset_target(double);
  double compute_scalar();
+  void write_restart(FILE *);
+  void restart(char *buf);
  virtual void *extract(const char *, int &);

 private:
--- a/src/fix_temp_csld.cpp
+++ b/src/fix_temp_csld.cpp
@ -49,6 +49,7 @@ FixTempCSLD::FixTempCSLD(LAMMPS *lmp, int narg, char **arg) :

  // CSLD thermostat should be applied every step

+  restart_global = 1;
  nevery = 1;
  scalar_flag = 1;
  global_freq = nevery;
@ -297,6 +298,46 @@ double FixTempCSLD::compute_scalar()
  return energy;
 }

+
+/* ----------------------------------------------------------------------
+   pack entire state of Fix into one write
+------------------------------------------------------------------------- */
+
+void FixTempCSLD::write_restart(FILE *fp)
+{
+  int nsize = (98+2+3)*comm->nprocs+2; // pRNG state per proc + nprocs + energy
+  double *list;
+  if (comm->me == 0) list = new double[nsize];
+  list[0] = energy;
+  list[1] = comm->nprocs;
+  double state[103];
+  random->get_state(state);
+  MPI_Gather(state,103,MPI_DOUBLE,list+2,103*comm->nprocs,MPI_DOUBLE,0,world);
+
+  if (comm->me == 0) {
+    int size = nsize * sizeof(double);
+    fwrite(&size,sizeof(int),1,fp);
+    fwrite(list,sizeof(double),nsize,fp);
+  }
+  if (comm->me == 0) delete[] list;
+}
+
+/* ----------------------------------------------------------------------
+   use state info from restart file to restart the Fix
+------------------------------------------------------------------------- */
+
+void FixTempCSLD::restart(char *buf)
+{
+  double *list = (double *) buf;
+
+  energy = list[0];
+  int nprocs = (int) list[1];
+  if (nprocs != comm->nprocs) {
+    if (comm->me == 0)
+      error->warning(FLERR,"Different number of procs. Cannot restore RNG state.");
+  } else random->set_state(list+2+comm->me*103);
+}
+
 /* ----------------------------------------------------------------------
   extract thermostat properties
 ------------------------------------------------------------------------- */
--- a/src/fix_temp_csld.h
+++ b/src/fix_temp_csld.h
@ -34,6 +34,8 @@ class FixTempCSLD : public Fix {
  int modify_param(int, char **);
  void reset_target(double);
  virtual double compute_scalar();
+  void write_restart(FILE *);
+  void restart(char *buf);
  virtual void *extract(const char *, int &);

 private:
--- a/src/fix_temp_csvr.cpp
+++ b/src/fix_temp_csvr.cpp
@ -126,6 +126,7 @@ FixTempCSVR::FixTempCSVR(LAMMPS *lmp, int narg, char **arg) :

  // CSVR thermostat should be applied every step

+  restart_global = 1;
  nevery = 1;
  scalar_flag = 1;
  global_freq = nevery;
@ -331,6 +332,45 @@ double FixTempCSVR::compute_scalar()
  return energy;
 }

+/* ----------------------------------------------------------------------
+   pack entire state of Fix into one write
+------------------------------------------------------------------------- */
+
+void FixTempCSVR::write_restart(FILE *fp)
+{
+  int nsize = (98+2+3)*comm->nprocs+2; // pRNG state per proc + nprocs + energy
+  double *list;
+  if (comm->me == 0) list = new double[nsize];
+  list[0] = energy;
+  list[1] = comm->nprocs;
+  double state[103];
+  random->get_state(state);
+  MPI_Gather(state,103,MPI_DOUBLE,list+2,103*comm->nprocs,MPI_DOUBLE,0,world);
+
+  if (comm->me == 0) {
+    int size = nsize * sizeof(double);
+    fwrite(&size,sizeof(int),1,fp);
+    fwrite(list,sizeof(double),nsize,fp);
+  }
+  if (comm->me == 0) delete[] list;
+}
+
+/* ----------------------------------------------------------------------
+   use state info from restart file to restart the Fix
+------------------------------------------------------------------------- */
+
+void FixTempCSVR::restart(char *buf)
+{
+  double *list = (double *) buf;
+
+  energy = list[0];
+  int nprocs = (int) list[1];
+  if (nprocs != comm->nprocs) {
+    if (comm->me == 0)
+      error->warning(FLERR,"Different number of procs. Cannot restore RNG state.");
+  } else random->set_state(list+2+comm->me*103);
+}
+
 /* ----------------------------------------------------------------------
   extract thermostat properties
 ------------------------------------------------------------------------- */
--- a/src/fix_temp_csvr.h
+++ b/src/fix_temp_csvr.h
@ -34,6 +34,8 @@ class FixTempCSVR : public Fix {
  int modify_param(int, char **);
  void reset_target(double);
  virtual double compute_scalar();
+  void write_restart(FILE *);
+  void restart(char *buf);
  virtual void *extract(const char *, int &);

 private:
--- a/src/pair_table.cpp
+++ b/src/pair_table.cpp
@ -458,25 +458,25 @@ void PairTable::read_table(Table *tb, char *file, char *keyword)
  }

  if (ferror)
-    error->warning(FLERR,fmt::format("{} of {} force values in table are "
+    error->warning(FLERR,fmt::format("{} of {} force values in table {} are "
                                     "inconsistent with -dE/dr.\n  Should "
                                     "only be flagged at inflection points",
-                                     ferror,tb->ninput));
+                                     ferror,tb->ninput,keyword));

  // warn if re-computed distance values differ from file values

  if (rerror)
-    error->warning(FLERR,fmt::format("{} of {} distance values in table with "
-                                     "relative error\n  over {} to "
+    error->warning(FLERR,fmt::format("{} of {} distance values in table {} "
+                                     "with relative error\n  over {} to "
                                     "re-computed values",
-                                     rerror,tb->ninput,EPSILONR));
+                                     rerror,tb->ninput,EPSILONR,keyword));

  // warn if data was read incompletely, e.g. columns were missing

  if (cerror)
-    error->warning(FLERR,fmt::format("{} of {} lines in table were "
+    error->warning(FLERR,fmt::format("{} of {} lines in table {} were "
                                     "incomplete\n  or could not be parsed "
-                                     "completely",cerror,tb->ninput));
+                                     "completely",cerror,tb->ninput,keyword));
 }

 /* ----------------------------------------------------------------------
--- a/src/random_mars.cpp
+++ b/src/random_mars.cpp
@ -16,6 +16,7 @@

 #include "random_mars.h"
 #include <cmath>
+#include <cstring>
 #include "error.h"
 #include "math_const.h"

@ -36,6 +37,7 @@ RanMars::RanMars(LAMMPS *lmp, int seed) : Pointers(lmp),

  save = 0;
  u = new double[97+1];
+  memset(u,0,98*sizeof(double));

  ij = (seed-1)/30082;
  kl = (seed-1) - 30082*ij;
@ -181,7 +183,7 @@ double RanMars::besselexp(double theta, double alpha, double cp)
 void RanMars::select_subset(bigint ntarget, int nmine, int *mark, int *next)
 {
  int mode,index,oldindex,newvalue,nflip,which,niter;
-  int active[2],first[2],last[2];
+  int active[2],first[2];
  int newactive[2],newfirst[2],newlast[2];
  bigint nmark,nflipall;
  bigint activeall[2],bsum[3],bsumall[3];
@ -191,8 +193,6 @@ void RanMars::select_subset(bigint ntarget, int nmine, int *mark, int *next)
  active[1] = 0;
  first[0] = 0;
  first[1] = -1;
-  last[0] = nmine-1;
-  last[1] = -1;

  bigint bnmine = nmine;
  bigint bnall;
@ -266,8 +266,6 @@ void RanMars::select_subset(bigint ntarget, int nmine, int *mark, int *next)
      active[1] = newactive[1];
      first[0] = newfirst[0];
      first[1] = newfirst[1];
-      last[0] = newlast[0];
-      last[1] = newlast[1];
    }

    // update nmark and activeall
@ -291,3 +289,31 @@ void RanMars::select_subset(bigint ntarget, int nmine, int *mark, int *next)
    //                          niter,nmark,nactiveall,thresh,nflipall);
  }
 }
+
+/* ----------------------------------------------------------------------
+   store state in buffer
+------------------------------------------------------------------------- */
+
+void RanMars::get_state(double *state)
+{
+  for (int i=0; i < 98; ++i) state[i] = u[i];
+  state[98] = i97;
+  state[99] = j97;
+  state[100]= c;
+  state[101]= cd;
+  state[102]= cm;
+}
+
+/* ----------------------------------------------------------------------
+   restore state from buffer
+------------------------------------------------------------------------- */
+
+void RanMars::set_state(double *state)
+{
+  for (int i=0; i < 98; ++i) u[i] = state[i];
+  i97 = state[98];
+  j97 = state[99];
+  c   = state[100];
+  cd  = state[101];
+  cm  = state[102];
+}
--- a/src/random_mars.h
+++ b/src/random_mars.h
@ -28,6 +28,8 @@ class RanMars : protected Pointers {
  double rayleigh(double sigma);
  double besselexp(double theta, double alpha, double cp);
  void select_subset(bigint, int, int *, int *);
+  void get_state(double *);
+  void set_state(double *);

 private:
  int save;
--- a/src/velocity.cpp
+++ b/src/velocity.cpp
@ -67,7 +67,7 @@ void Velocity::command(int narg, char **arg)

  // check if velocities of atoms in rigid bodies are updated

-  if (modify->check_rigid_group_overlap(groupbit))
+  if (modify->check_rigid_group_overlap(groupbit) && (comm->me == 0))
    error->warning(FLERR,"Changing velocities of atoms in rigid bodies. "
                     "This has no effect unless rigid bodies are rebuild");

@ -200,7 +200,7 @@ void Velocity::create(double t_desired, int seed)
  // initialize temperature computation(s)
  // warn if groups don't match

-  if (igroup != temperature->igroup && comm->me == 0)
+  if ((igroup != temperature->igroup) && (comm->me == 0))
    error->warning(FLERR,"Mismatch between velocity and compute groups");
  temperature->init();
  temperature->setup();
@ -596,7 +596,7 @@ void Velocity::scale(int /*narg*/, char **arg)
  // initialize temperature computation
  // warn if groups don't match

-  if (igroup != temperature->igroup && comm->me == 0)
+  if ((igroup != temperature->igroup) && (comm->me == 0))
    error->warning(FLERR,"Mismatch between velocity and compute groups");
  temperature->init();
  temperature->setup();
--- a/unittest/CMakeLists.txt
+++ b/unittest/CMakeLists.txt
@ -1,9 +1,9 @@
 include(GTest)

-add_subdirectory(force-styles)
 add_subdirectory(utils)
 add_subdirectory(formats)
 add_subdirectory(commands)
+add_subdirectory(force-styles)

 find_package(ClangFormat 8.0)

--- a/unittest/commands/test_reset_ids.cpp
+++ b/unittest/commands/test_reset_ids.cpp
@ -660,6 +660,8 @@ TEST_F(ResetIDsTest, TopologyData)

 TEST_F(ResetIDsTest, DeathTests)
 {
+    if (lmp->atom->natoms == 0) GTEST_SKIP();
+
    TEST_FAILURE(".*ERROR: Illegal reset_mol_ids command.*", lmp->input->one("reset_mol_ids"););
    TEST_FAILURE(".*ERROR: Illegal reset_mol_ids command.*",
                 lmp->input->one("reset_mol_ids all offset 1 1"););
--- a/unittest/force-styles/CMakeLists.txt
+++ b/unittest/force-styles/CMakeLists.txt
@ -114,3 +114,16 @@ foreach(TEST ${KSPACE_TESTS})
  add_test(NAME ${TNAME} COMMAND test_pair_style ${TEST} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
  set_tests_properties(${TNAME} PROPERTIES ENVIRONMENT "LAMMPS_POTENTIALS=${LAMMPS_POTENTIALS_DIR};PYTHONPATH=${TEST_INPUT_FOLDER}:$ENV{PYTHONPATH}")
 endforeach()
+
+# tester for timestepping fixes
+add_executable(test_fix_timestep test_fix_timestep.cpp)
+target_link_libraries(test_fix_timestep PRIVATE lammps style_tests)
+
+# tests for timestep related fixes (time integration, thermostat, force manipulation, constraints/restraints)
+file(GLOB FIX_TIMESTEP_TESTS LIST_DIRECTORIES false ${TEST_INPUT_FOLDER}/fix-timestep-*.yaml)
+foreach(TEST ${FIX_TIMESTEP_TESTS})
+  string(REGEX REPLACE "^.*fix-timestep-(.*)\.yaml" "FixTimestep:\\1" TNAME ${TEST})
+  add_test(NAME ${TNAME} COMMAND test_fix_timestep ${TEST} WORKING_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
+  set_tests_properties(${TNAME} PROPERTIES ENVIRONMENT "LAMMPS_POTENTIALS=${LAMMPS_POTENTIALS_DIR};PYTHONPATH=${TEST_INPUT_FOLDER}:$ENV{PYTHONPATH}")
+endforeach()
+
--- a/unittest/force-styles/check_tests.py
+++ b/unittest/force-styles/check_tests.py
@ -55,6 +55,7 @@ kspace = {}
 pair = {}

 style_pattern = re.compile("(.+)Style\((.+),(.+)\)")
+upper = re.compile("[A-Z]+")
 gpu = re.compile("(.+)/gpu$")
 intel = re.compile("(.+)/intel$")
 kokkos = re.compile("(.+)/kk$")
@ -85,7 +86,7 @@ for header in headers:
            for m in matches:
                # skip over internal styles w/o explicit documentation
                style = m[1]
-                if style.isupper():
+                if upper.match(style):
                    continue

                # detect, process, and flag suffix styles:
@ -131,6 +132,8 @@ for header in headers:
                    register_style(kspace,style,info)
                elif m[0] == 'Pair':
                    register_style(pair,style,info)
+                elif m[0] == 'Fix':
+                    register_style(fix,style,info)



@ -179,6 +182,8 @@ counter += check_tests('improper',improper,'improper-*.yaml',
                       '.*improper_style:\s*((\S+).*)?')
 counter += check_tests('kspace',kspace,'kspace-*.yaml',
                       '.*kspace_style\s*((\S+).*)?')
+counter += check_tests('fix',fix,'fix-*.yaml',
+                       '  fix\s+((\S+)\s*)?')

-total = len(pair)+len(bond)+len(angle)+len(dihedral)+len(improper)+len(kspace)
+total = len(pair)+len(bond)+len(angle)+len(dihedral)+len(improper)+len(kspace)+len(fix)
 print(f"\nTotal tests missing: {counter} of {total}")
--- a/unittest/force-styles/error_stats.h
+++ b/unittest/force-styles/error_stats.h
@ -29,6 +29,7 @@ public:
    double dev() const;
    double max() const { return maxerr; }
    double idx() const { return maxidx; }
+    bool has_data() const { return num > 0; }

 private:
    double sum, sumsq, maxerr;
--- a/unittest/force-styles/test_config.h
+++ b/unittest/force-styles/test_config.h
@ -58,15 +58,21 @@ public:
    double run_coul;
    stress_t init_stress;
    stress_t run_stress;
+    double global_scalar;
+    std::vector<double> global_vector;
    std::vector<coord_t> init_forces;
    std::vector<coord_t> run_forces;
+    std::vector<coord_t> run_pos;
+    std::vector<coord_t> restart_pos;
+    std::vector<coord_t> run_vel;
+    std::vector<coord_t> restart_vel;

    TestConfig() :
        lammps_version(""), date_generated(""), basename(""), epsilon(1.0e-14), input_file(""),
        pair_style("zero"), bond_style("zero"), angle_style("zero"), dihedral_style("zero"),
        improper_style("zero"), kspace_style("none"), natoms(0), init_energy(0), run_energy(0),
        init_vdwl(0), run_vdwl(0), init_coul(0), run_coul(0), init_stress({0, 0, 0, 0, 0, 0}),
-        run_stress({0, 0, 0, 0, 0, 0})
+        run_stress({0, 0, 0, 0, 0, 0}), global_scalar(0)
    {
        prerequisites.clear();
        pre_commands.clear();
@ -79,6 +85,11 @@ public:
        extract.clear();
        init_forces.clear();
        run_forces.clear();
+        run_pos.clear();
+        restart_pos.clear();
+        run_vel.clear();
+        restart_vel.clear();
+        global_vector.clear();
    }
    virtual ~TestConfig(){};

--- a/unittest/force-styles/test_config_reader.cpp
+++ b/unittest/force-styles/test_config_reader.cpp
@ -40,6 +40,8 @@ TestConfigReader::TestConfigReader(TestConfig &config) : YamlReader(), config(co
    consumers["run_stress"]     = &TestConfigReader::run_stress;
    consumers["init_forces"]    = &TestConfigReader::init_forces;
    consumers["run_forces"]     = &TestConfigReader::run_forces;
+    consumers["run_pos"]        = &TestConfigReader::run_pos;
+    consumers["run_vel"]        = &TestConfigReader::run_vel;

    consumers["pair_style"] = &TestConfigReader::pair_style;
    consumers["pair_coeff"] = &TestConfigReader::pair_coeff;
@ -48,6 +50,9 @@ TestConfigReader::TestConfigReader(TestConfig &config) : YamlReader(), config(co
    consumers["run_vdwl"]   = &TestConfigReader::run_vdwl;
    consumers["run_coul"]   = &TestConfigReader::run_coul;

+    consumers["global_scalar"] = &TestConfigReader::global_scalar;
+    consumers["global_vector"] = &TestConfigReader::global_vector;
+
    consumers["bond_style"]  = &TestConfigReader::bond_style;
    consumers["bond_coeff"]  = &TestConfigReader::bond_coeff;
    consumers["angle_style"] = &TestConfigReader::angle_style;
@ -176,6 +181,36 @@ void TestConfigReader::run_forces(const yaml_event_t &event)
    }
 }

+void TestConfigReader::run_pos(const yaml_event_t &event)
+{
+    config.run_pos.clear();
+    config.run_pos.resize(config.natoms + 1);
+    std::stringstream data((char *)event.data.scalar.value);
+    std::string line;
+
+    while (std::getline(data, line, '\n')) {
+        int tag;
+        coord_t xyz;
+        sscanf(line.c_str(), "%d %lg %lg %lg", &tag, &xyz.x, &xyz.y, &xyz.z);
+        config.run_pos[tag] = xyz;
+    }
+}
+
+void TestConfigReader::run_vel(const yaml_event_t &event)
+{
+    config.run_vel.clear();
+    config.run_vel.resize(config.natoms + 1);
+    std::stringstream data((char *)event.data.scalar.value);
+    std::string line;
+
+    while (std::getline(data, line, '\n')) {
+        int tag;
+        coord_t xyz;
+        sscanf(line.c_str(), "%d %lg %lg %lg", &tag, &xyz.x, &xyz.y, &xyz.z);
+        config.run_vel[tag] = xyz;
+    }
+}
+
 void TestConfigReader::pair_style(const yaml_event_t &event)
 {
    config.pair_style = (char *)event.data.scalar.value;
@ -267,3 +302,21 @@ void TestConfigReader::run_energy(const yaml_event_t &event)
 {
    config.run_energy = atof((char *)event.data.scalar.value);
 }
+
+void TestConfigReader::global_scalar(const yaml_event_t &event)
+{
+    config.global_scalar = atof((char *)event.data.scalar.value);
+}
+
+void TestConfigReader::global_vector(const yaml_event_t &event)
+{
+    std::stringstream data((char *)event.data.scalar.value);
+    config.global_vector.clear();
+    double value;
+    std::size_t num;
+    data >> num;
+    for (std::size_t i = 0; i < num; ++i) {
+        data >> value;
+        config.global_vector.push_back(value);
+    }
+}
--- a/unittest/force-styles/test_config_reader.h
+++ b/unittest/force-styles/test_config_reader.h
@ -36,6 +36,8 @@ public:
    void run_stress(const yaml_event_t &event);
    void init_forces(const yaml_event_t &event);
    void run_forces(const yaml_event_t &event);
+    void run_pos(const yaml_event_t &event);
+    void run_vel(const yaml_event_t &event);
    void pair_style(const yaml_event_t &event);
    void pair_coeff(const yaml_event_t &event);
    void bond_style(const yaml_event_t &event);
@ -49,6 +51,8 @@ public:
    void run_coul(const yaml_event_t &event);
    void init_energy(const yaml_event_t &event);
    void run_energy(const yaml_event_t &event);
+    void global_scalar(const yaml_event_t &event);
+    void global_vector(const yaml_event_t &event);
 };

 #endif
--- a/unittest/force-styles/test_error_stats.cpp
+++ b/unittest/force-styles/test_error_stats.cpp
@ -29,12 +29,14 @@ TEST(ErrorStats, test)
    ASSERT_EQ(out.str(), "Average:  5.800e-01 StdDev:  7.305e-01 MaxErr:  2.000e+00 @ item: 3.0");

    stats.reset();
+    ASSERT_EQ(stats.has_data(), false);
    ASSERT_DOUBLE_EQ(stats.avg(), 0.0);
    ASSERT_DOUBLE_EQ(stats.dev(), 0.0);
    ASSERT_DOUBLE_EQ(stats.max(), 0.0);
    ASSERT_EQ(stats.idx(), -1);

    stats.add(1.0);
+    ASSERT_EQ(stats.has_data(), true);
    ASSERT_DOUBLE_EQ(stats.avg(), 1.0);
    ASSERT_DOUBLE_EQ(stats.dev(), 0.0);
    ASSERT_DOUBLE_EQ(stats.max(), 1.0);
--- a/unittest/force-styles/test_fix_timestep.cpp
+++ b/unittest/force-styles/test_fix_timestep.cpp
--- a/unittest/force-styles/test_main.cpp
+++ b/unittest/force-styles/test_main.cpp
@ -102,13 +102,16 @@ int main(int argc, char **argv)
        if (strcmp(argv[iarg], "-g") == 0) {
            if (iarg + 1 < argc) {
                generate_yaml_file(argv[iarg + 1], test_config);
+                MPI_Finalize();
                return 0;
            } else {
                usage(std::cerr, argv[0]);
+                MPI_Finalize();
                return 1;
            }
        } else if (strcmp(argv[iarg], "-u") == 0) {
            generate_yaml_file(argv[1], test_config);
+            MPI_Finalize();
            return 0;
        } else if (strcmp(argv[iarg], "-d") == 0) {
            if (iarg + 1 < argc) {
@ -116,6 +119,7 @@ int main(int argc, char **argv)
                iarg += 2;
            } else {
                usage(std::cerr, argv[0]);
+                MPI_Finalize();
                return 1;
            }
        } else if (strcmp(argv[iarg], "-s") == 0) {
@ -127,6 +131,7 @@ int main(int argc, char **argv)
        } else {
            std::cerr << "unknown option: " << argv[iarg] << "\n\n";
            usage(std::cerr, argv[0]);
+            MPI_Finalize();
            return 1;
        }
    }
--- a/unittest/force-styles/test_pair_style.cpp
+++ b/unittest/force-styles/test_pair_style.cpp
@ -1107,8 +1107,7 @@ TEST(PairStyle, single)
        (test_config.pair_style.substr(0, 14) == "yukawa/colloid") ||
        (test_config.pair_style.substr(0, 3) == "eam") ||
        ((test_config.pair_style.substr(0, 6) == "hybrid") &&
-         (test_config.pair_style.find("eam") != std::string::npos))
-        ) {
+         (test_config.pair_style.find("eam") != std::string::npos))) {
        if (!verbose) ::testing::internal::CaptureStdout();
        cleanup_lammps(lmp, test_config);
        if (!verbose) ::testing::internal::GetCapturedStdout();
--- a/unittest/force-styles/tests/atomic-pair-edip.yaml
+++ b/unittest/force-styles/tests/atomic-pair-edip.yaml
@ -1,7 +1,7 @@
 ---
 lammps_version: 21 Jul 2020
 date_generated: Fri Aug  7 16:11:57 202
-epsilon: 1e-14
+epsilon: 2e-14
 prerequisites: ! |
  pair edip
 pre_commands: ! |
--- a/unittest/force-styles/tests/fix-timestep-addforce-const.yaml
+++ b/unittest/force-styles/tests/fix-timestep-addforce-const.yaml
@ -0,0 +1,77 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Tue Aug 11 20:56:35 202
+epsilon: 2e-13
+prerequisites: ! |
+  atom full
+  fix addforce
+pre_commands: ! ""
+post_commands: ! |
+  fix move all nve
+  fix test solute addforce 0.0 -0.1 0.1
+input_file: in.fourmol
+natoms: 29
+global_scalar: 1.48901835738129
+global_vector: ! |-
+  3 0.030822392996626036 0.026014193882019754 -0.017708991389909556
+run_pos: ! |2
+    1 -2.7045575291334861e-01  2.4912098953869757e+00 -1.6695239815574214e-01
+    2  3.1004076900710170e-01  2.9612149597462425e+00 -8.5464329005027972e-01
+    3 -7.0398549308743119e-01  1.2305439518786667e+00 -6.2776812583732400e-01
+    4 -1.5818160726875390e+00  1.4837199951274893e+00 -1.2538503621778578e+00
+    5 -9.0719748669903200e-01  9.2650033697311973e-01  3.9956266031649879e-01
+    6  2.4831714249110262e-01  2.8312325631591767e-01 -1.2314165454625041e+00
+    7  3.4143527198959711e-01 -2.2651747674360529e-02 -2.5292238033565768e+00
+    8  1.1743553514271237e+00 -4.8863828453992741e-01 -6.3782817835070349e-01
+    9  1.3800522445502728e+00 -2.5276822789361231e-01  2.8356018210481976e-01
+   10  2.0510765111429961e+00 -1.4604133270429198e+00 -9.8323043580441027e-01
+   11  1.7878031588883598e+00 -1.9922071845945071e+00 -1.8890394822792633e+00
+   12  3.0063007413447411e+00 -4.9014063242955885e-01 -1.6231827019640992e+00
+   13  4.0515402229636264e+00 -8.9204090546353654e-01 -1.6399797487882732e+00
+   14  2.6066963018347171e+00 -4.1791325385826189e-01 -2.6633797762015425e+00
+   15  2.9695287113240152e+00  5.5420546275525007e-01 -1.2341814098635149e+00
+   16  2.6747030089515893e+00 -2.4124189004358674e+00 -2.3428869709464669e-02
+   17  2.2153577487661584e+00 -2.0898037210104183e+00  1.1963203850079958e+00
+   18  2.1369701704121455e+00  3.0158507413641966e+00 -3.5179348337229994e+00
+   19  1.5355837136088100e+00  2.6255292355377717e+00 -4.2353987779882338e+00
+   20  2.7727573005679371e+00  3.6923910449611110e+00 -3.9330842459134390e+00
+   21  4.9040128073204006e+00 -4.0752348172958719e+00 -3.6210314709889815e+00
+   22  4.3582355554440877e+00 -4.2126119427287128e+00 -4.4612844196313990e+00
+   23  5.7439382849307599e+00 -3.5821957939275113e+00 -3.8766361295935736e+00
+   24  2.0689243582419619e+00  3.1513346907267743e+00  3.1550389754827148e+00
+   25  1.3045351331489012e+00  3.2665125705839713e+00  2.5111855257429738e+00
+   26  2.5809237402711087e+00  4.0117602605482601e+00  3.2212060529089812e+00
+   27 -1.9611343130352876e+00 -4.3563411931356626e+00  2.1098293115521889e+00
+   28 -2.7473562684513193e+00 -4.0200819932379153e+00  1.5830052163433885e+00
+   29 -1.3126000191359226e+00 -3.5962518039482334e+00  2.2746342468737333e+00
+run_vel: ! |2
+    1  8.1702613218438691e-03  1.6510191351429417e-02  4.7964973237771503e-03
+    2  5.4511084170875343e-03  5.1590481528437813e-03 -1.4175058774793692e-03
+    3 -8.2297881733875439e-03 -1.2933678261753652e-02 -4.0910944229037285e-03
+    4 -3.7701876602396953e-03 -6.5929809185369939e-03 -1.0979051123824390e-03
+    5 -1.1021655940056645e-02 -9.9111987493572112e-03 -2.8208515585563172e-03
+    6 -3.9676769272842236e-02  4.6810118626188314e-02  3.7155184099431124e-02
+    7  9.1033245554758080e-04 -1.0133704610200299e-02 -5.1562858164992204e-02
+    8  7.9067086761695892e-03 -3.3567238353401636e-03  3.4563427326757518e-02
+    9  1.5640463507800002e-03  3.7153745906232053e-03  1.5067137863525135e-02
+   10  2.9201431684716742e-02 -2.9256524162078218e-02 -1.5011015513636336e-02
+   11 -4.7836707031183607e-03 -3.7689744526784260e-03 -2.3257693833597559e-03
+   12  2.2697215661243897e-03 -3.5503408953511771e-04 -3.0568221042131718e-03
+   13  2.7530266001101656e-03  5.7964078805919205e-03 -7.7394765650209171e-04
+   14  3.5245514557562165e-03 -5.8145427341994562e-03 -3.9275617105511392e-03
+   15 -1.8548103902428440e-03 -5.8759259808655083e-03  6.3145508812191310e-03
+   16  1.8681562217261326e-02 -1.3269471066222347e-02 -4.5631826406699355e-02
+   17 -1.2896316924809444e-02  9.7475788915801498e-03  3.7301887298077194e-02
+   18 -8.0065794732626385e-04 -8.6270472984577718e-04 -1.4483040728194251e-03
+   19  1.2452390837669909e-03 -2.5061097114590261e-03  7.2998631002926129e-03
+   20  3.5930060230919166e-03  3.6938860311325015e-03  3.2322732685912069e-03
+   21 -1.4689220371368486e-03 -2.7352129777820513e-04  7.0581624254054305e-04
+   22 -7.0694199254559926e-03 -4.2577148925067674e-03  2.8079117615819173e-04
+   23  6.0446963117369709e-03 -1.4000131614987045e-03  2.5819754847190117e-03
+   24  3.1926367840560363e-04 -9.9445664816168633e-04  1.4999996925784762e-04
+   25  1.3789754450351514e-04 -4.4335894890997355e-03 -8.1808136802931375e-04
+   26  2.0485904034793470e-03  2.7813358633281375e-03  4.3245727149043870e-03
+   27  4.5604120382313504e-04 -1.0305523020532397e-03  2.1188058344304351e-04
+   28 -6.2544520861381259e-03  1.4127711176493136e-03 -1.8429821884921316e-03
+   29  6.4110631547740983e-04  3.1273432720868841e-03  3.7253671104628787e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-addforce-variable.yaml
+++ b/unittest/force-styles/tests/fix-timestep-addforce-variable.yaml
@ -0,0 +1,82 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Tue Aug 11 20:56:35 202
+epsilon: 2e-13
+prerequisites: ! |
+  atom full
+  fix addforce
+pre_commands: ! ""
+post_commands: ! |
+  fix init all store/state 0 x y z
+  variable xforce delete
+  variable xforce atom f_init[1]
+  variable zforce delete
+  variable zforce equal 0.1*step/10.0
+  fix move all nve
+  fix test solute addforce v_xforce 0.0 v_zforce
+input_file: in.fourmol
+natoms: 29
+global_scalar: -66.6128081721324
+global_vector: ! |-
+  3 0.030822805860552194 0.026012717110660333 -0.017710664092739137
+run_pos: ! |2
+    1 -2.7047214228789879e-01  2.4912159473897288e+00 -1.6695741351125751e-01
+    2  3.1010217675350321e-01  2.9612343643897283e+00 -8.5465678502037923e-01
+    3 -7.0403575539675045e-01  1.2305513713119018e+00 -6.2777371590783770e-01
+    4 -1.5821400298238728e+00  1.4837402879631465e+00 -1.2538644175974110e+00
+    5 -9.0738248321725767e-01  9.2652118661051119e-01  3.9954717998547740e-01
+    6  2.4833938838692704e-01  2.8312848343353764e-01 -1.2314198266861847e+00
+    7  3.4145305574459789e-01 -2.2646551615904693e-02 -2.5292277033981856e+00
+    8  1.1744251519295958e+00 -4.8863301930795239e-01 -6.3783420180106931e-01
+    9  1.3803393322923716e+00 -2.5274719088138620e-01  2.8354262280984910e-01
+   10  2.0512157806659483e+00 -1.4604034995894550e+00 -9.8323457702970984e-01
+   11  1.7881766053556223e+00 -1.9921867592459330e+00 -1.8890557966324570e+00
+   12  3.0065163851107513e+00 -4.9013454995145816e-01 -1.6231872062008903e+00
+   13  4.0523716162518593e+00 -8.9201902994109461e-01 -1.6399944550397565e+00
+   14  2.6072370808739733e+00 -4.1789116991871833e-01 -2.6633963232657543e+00
+   15  2.9701454639399292e+00  5.5422639267898544e-01 -1.2341975484787577e+00
+   16  2.6748871049483789e+00 -2.4124111330493521e+00 -2.3431784517031026e-02
+   17  2.2154747990656891e+00 -2.0897989887607591e+00  1.1963148502274976e+00
+   18  2.1369701704176829e+00  3.0158507413681335e+00 -3.5179348337252407e+00
+   19  1.5355837136089958e+00  2.6255292355383033e+00 -4.2353987779886255e+00
+   20  2.7727573005681436e+00  3.6923910449611030e+00 -3.9330842459134483e+00
+   21  4.9040128073163958e+00 -4.0752348172839117e+00 -3.6210314709779454e+00
+   22  4.3582355554441445e+00 -4.2126119427283166e+00 -4.4612844196308510e+00
+   23  5.7439382849302527e+00 -3.5821957939267821e+00 -3.8766361295928178e+00
+   24  2.0689243582437542e+00  3.1513346907275186e+00  3.1550389754841301e+00
+   25  1.3045351331496602e+00  3.2665125705847990e+00  2.5111855257446942e+00
+   26  2.5809237402712069e+00  4.0117602605483258e+00  3.2212060529090598e+00
+   27 -1.9611343130422572e+00 -4.3563411931406684e+00  2.1098293115555511e+00
+   28 -2.7473562684515755e+00 -4.0200819932380565e+00  1.5830052163434851e+00
+   29 -1.3126000191366660e+00 -3.5962518039487934e+00  2.2746342468743648e+00
+run_vel: ! |2
+    1  8.1542005804048114e-03  1.6516352657195144e-02  4.7916994861873716e-03
+    2  5.5108616996518527e-03  5.1769592855304752e-03 -1.4262044196006701e-03
+    3 -8.2819560524694975e-03 -1.2925874484803790e-02 -4.0962172584282129e-03
+    4 -4.0886380039043026e-03 -6.5733036630979845e-03 -1.1077208107759873e-03
+    5 -1.1204698339013554e-02 -9.8903762469767197e-03 -2.8335724171420786e-03
+    6 -3.9653324695987140e-02  4.6814090441761887e-02  3.7154219827738325e-02
+    7  9.2811228899244145e-04 -1.0128521447666933e-02 -5.1566014310509153e-02
+    8  7.9768414397017682e-03 -3.3521215541620886e-03  3.4557180732453542e-02
+    9  1.8506084396989573e-03  3.7365307043657862e-03  1.5049937691527137e-02
+   10  2.9339781785645530e-02 -2.9244335397845489e-02 -1.5013285041501756e-02
+   11 -4.4111732898708574e-03 -3.7490441708152595e-03 -2.3402341830182269e-03
+   12  2.4919774686993339e-03 -3.4986602016114646e-04 -3.0596868750942985e-03
+   13  3.5708757570142549e-03  5.8192695094192127e-03 -7.8509643584213180e-04
+   14  4.0624997491302594e-03 -5.7912127152414828e-03 -3.9424433676611033e-03
+   15 -1.2427000878928462e-03 -5.8549223934944352e-03  6.3005021988472203e-03
+   16  1.8865114672276220e-02 -1.3261139374878017e-02 -4.5632510336419303e-02
+   17 -1.2778996290317002e-02  9.7520044246185329e-03  3.7296098445722708e-02
+   18 -8.0065793587999099e-04 -8.6270472146121331e-04 -1.4483040775306573e-03
+   19  1.2452390841875935e-03 -2.5061097103150493e-03  7.2998630994791933e-03
+   20  3.5930060235755922e-03  3.6938860311851785e-03  3.2322732685174278e-03
+   21 -1.4689220453590402e-03 -2.7352127317486851e-04  7.0581626525379880e-04
+   22 -7.0694199252635138e-03 -4.2577148916858000e-03  2.8079117743316296e-04
+   23  6.0446963107027478e-03 -1.4000131600045436e-03  2.5819754862959378e-03
+   24  3.1926368204184148e-04 -9.9445664667548433e-04  1.4999997209784617e-04
+   25  1.3789754604908935e-04 -4.4335894874218615e-03 -8.1808136451897351e-04
+   26  2.0485904036966728e-03  2.7813358634892773e-03  4.3245727150655168e-03
+   27  4.5604118959923195e-04 -1.0305523122762120e-03  2.1188059030274769e-04
+   28 -6.2544520866959210e-03  1.4127711173635808e-03 -1.8429821883176730e-03
+   29  6.4110631389697711e-04  3.1273432708352981e-03  3.7253671117315453e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-aveforce-const.yaml
+++ b/unittest/force-styles/tests/fix-timestep-aveforce-const.yaml
@ -0,0 +1,76 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Tue Aug 11 20:59:48 202
+epsilon: 2e-13
+prerequisites: ! |
+  atom full
+  fix aveforce
+pre_commands: ! ""
+post_commands: ! |
+  fix move all nve
+  fix test solute aveforce 0.0 -0.1 0.1
+input_file: in.fourmol
+natoms: 29
+global_vector: ! |-
+  3 0.030693239277496787 0.026836713504508225 -0.017872771454378267
+run_pos: ! |2
+    1 -2.7837937276378577e-01  2.4738323337395633e+00 -1.7244628118937513e-01
+    2  3.0739712238693778e-01  2.9607606438663985e+00 -8.4971558628080046e-01
+    3 -6.9690101126084858e-01  1.2472621905952943e+00 -6.2300348438124675e-01
+    4 -1.5790176115308630e+00  1.4890051885382072e+00 -1.2569330199852327e+00
+    5 -8.9737740636582297e-01  9.3716922702553496e-01  4.0243602458027911e-01
+    6  2.9350792503004042e-01  2.2973704675580464e-01 -1.2827110266930783e+00
+    7  3.3997804713002810e-01 -1.0668179410931006e-02 -2.4648504997159280e+00
+    8  1.1649000306414594e+00 -4.8538782401639990e-01 -6.7628963324595071e-01
+    9  1.3802414668448064e+00 -2.5900562603021171e-01  2.7102062739419147e-01
+   10  2.0194286609797985e+00 -1.4274129376624451e+00 -9.6779510337284758e-01
+   11  1.7922388743932793e+00 -1.9901831169119615e+00 -1.8898772827854291e+00
+   12  3.0051950803427370e+00 -4.9053937459745156e-01 -1.6214531896525444e+00
+   13  4.0528786674689306e+00 -8.9433183344016831e-01 -1.6399905570763349e+00
+   14  2.6030389141568233e+00 -4.1604937323184987e-01 -2.6632873866075890e+00
+   15  2.9669715603426763e+00  5.5696161645207065e-01 -1.2373368321417231e+00
+   16  2.6515621187465719e+00 -2.3967182309150830e+00  3.5904361799912736e-02
+   17  2.2323104172823971e+00 -2.1015643262334032e+00  1.1508699165079972e+00
+   18  2.1369701683126636e+00  3.0158507352292498e+00 -3.5179348302759084e+00
+   19  1.5355837134891335e+00  2.6255292349555996e+00 -4.2353987775907820e+00
+   20  2.7727573004960764e+00  3.6923910448057331e+00 -3.9330842458523567e+00
+   21  4.9040128097611282e+00 -4.0752348192998742e+00 -3.6210314741040888e+00
+   22  4.3582355555035486e+00 -4.2126119428105140e+00 -4.4612844198387114e+00
+   23  5.7439382850855170e+00 -3.5821957939653362e+00 -3.8766361297558971e+00
+   24  2.0689243589260014e+00  3.1513346914908205e+00  3.1550389767665203e+00
+   25  1.3045351340666116e+00  3.2665125708708889e+00  2.5111855275754800e+00
+   26  2.5809237403634482e+00  4.0117602606068141e+00  3.2212060530163864e+00
+   27 -1.9611343134182779e+00 -4.3563411935660996e+00  2.1098293111593480e+00
+   28 -2.7473562684449138e+00 -4.0200819932443128e+00  1.5830052163349162e+00
+   29 -1.3126000190352287e+00 -3.5962518039727378e+00  2.2746342468394127e+00
+run_vel: ! |2
+    1  7.7878588734526198e-04  5.8382345680427130e-04 -2.1588360870901697e-04
+    2  2.7133298635754447e-03  4.6080941432587817e-03  3.6012143490662431e-03
+    3 -1.2735533433080959e-03  1.6040104178824128e-03 -3.2928787663304100e-04
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+   29  6.4110649930657559e-04  3.1273432105699108e-03  3.7253670414334056e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-aveforce-variable.yaml
+++ b/unittest/force-styles/tests/fix-timestep-aveforce-variable.yaml
@ -0,0 +1,81 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Tue Aug 11 20:59:48 202
+epsilon: 2e-13
+prerequisites: ! |
+  atom full
+  fix aveforce
+pre_commands: ! ""
+post_commands: ! |
+  fix init all store/state 0 x y z
+  variable xforce delete
+  #  variable xforce atom f_init[1]
+  variable zforce delete
+  variable zforce equal 0.1*step/10.0
+  fix move all nve
+  fix test solute aveforce 0.0 0.0 v_zforce
+input_file: in.fourmol
+natoms: 29
+global_vector: ! |-
+  3 0.030693295891580874 0.026836837377516076 -0.017872935896505737
+run_pos: ! |2
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+   29 -1.3126000190352873e+00 -3.5962518039727915e+00  2.2746342468394607e+00
+run_vel: ! |2
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+   23  6.0446966473247238e-03 -1.4000132185192382e-03  2.5819751444644172e-03
+   24  3.1926504141381389e-04 -9.9445515800801552e-04  1.5000252615930676e-04
+   25  1.3789938340469859e-04 -4.4335889211184667e-03 -8.1807768613931969e-04
+   26  2.0485906001419412e-03  2.7813359981542908e-03  4.3245729315573517e-03
+   27  4.5604045784400024e-04 -1.0305531431206094e-03  2.1187980985975486e-04
+   28 -6.2544520800211943e-03  1.4127711081968837e-03 -1.8429822100071731e-03
+   29  6.4110649918605221e-04  3.1273432104571073e-03  3.7253670415284034e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-nph.yaml
+++ b/unittest/force-styles/tests/fix-timestep-nph.yaml
@ -0,0 +1,76 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 07:12:15 202
+epsilon: 2e-13
+prerequisites: ! |
+  atom full
+  fix nph
+pre_commands: ! ""
+post_commands: ! |
+  fix test solute nph aniso 1.0 1.0 100.0 ptemp ${t_target} fixedpoint 0.0 0.0 0.0 couple xy
+input_file: in.fourmol
+natoms: 29
+global_scalar: 157.324342558061
+global_vector: ! |-
+  24 0.03782582730845563 0.03782582730845563 0.08149262752796986 0.028119558903421393 0.028119558903421393 0.0527171493109954 0.10922307816947409 0.0034329971508844604 -0.00019663936227634895 0.16528845193168182 0.011258118934021979 -0.0001767050030808935 0.002791882968285112 0.002791882968285112 0.002791882968285112 23.569551012162435 23.569551012162435 82.8396274600218 0.021704883273300262 0.000682207493931851 -3.9076305819928785e-05 27.145514121895616 0.12593449698077608 3.1024924904494816e-05
+run_pos: ! |2
+    1 -2.8141343498751503e-01  2.5848081694761129e+00 -1.8309382462779311e-01
+    2  3.1986473504266399e-01  3.0737731697045190e+00 -9.2489246315700946e-01
+    3 -7.2998464504762772e-01  1.2804424876519276e+00 -6.7969392967526154e-01
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+run_vel: ! |2
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+   23  2.4209481134686401e-04 -4.5457709985051130e-03  2.7663581642115042e-03
+   24  2.5447450568861086e-04  4.8412447786110117e-04 -4.8021914527341357e-04
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+   27 -2.6510179146429716e-04  3.6306203629019116e-04 -5.6235585400647747e-04
+   28 -2.3068708109787484e-04 -8.5663070212203200e-04  2.1302563179109169e-03
+   29 -2.5054744388303732e-03 -1.6773997805290820e-04  2.8436699761004796e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-npt_aniso.yaml
+++ b/unittest/force-styles/tests/fix-timestep-npt_aniso.yaml
@ -0,0 +1,76 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 07:12:15 202
+epsilon: 2e-12
+prerequisites: ! |
+  atom full
+  fix npt
+pre_commands: ! ""
+post_commands: ! |
+  fix test solute npt temp 50.0 ${t_target} 1.0 aniso 1.0 1.0 100.0 drag 0.01 flip no
+input_file: in.fourmol
+natoms: 29
+global_scalar: 343.095604765377
+global_vector: ! |-
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+run_pos: ! |2
+    1 -3.8261786782382412e-01  2.6468375260657648e+00 -1.1358866558857095e-01
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+...
--- a/unittest/force-styles/tests/fix-timestep-npt_iso.yaml
+++ b/unittest/force-styles/tests/fix-timestep-npt_iso.yaml
@ -0,0 +1,76 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 07:12:15 202
+epsilon: 5e-13
+prerequisites: ! |
+  atom full
+  fix npt
+pre_commands: ! ""
+post_commands: ! |
+  fix test solute npt temp 50.0 ${t_target} 1.0 iso 1.0 1.0 100.0 dilate solute
+input_file: in.fourmol
+natoms: 29
+global_scalar: 394.052580100464
+global_vector: ! |-
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+...
--- a/unittest/force-styles/tests/fix-timestep-npt_tri.yaml
+++ b/unittest/force-styles/tests/fix-timestep-npt_tri.yaml
@ -0,0 +1,77 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 07:12:15 202
+epsilon: 5e-12
+prerequisites: ! |
+  atom full
+  fix npt
+pre_commands: ! ""
+post_commands: ! |
+  change_box all triclinic
+  fix test solute npt temp 50.0 ${t_target} 1.0 tri 1.0 1.0 100.0 nreset 2
+input_file: in.fourmol
+natoms: 29
+global_scalar: 354.174797856098
+global_vector: ! |-
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+   28 -2.3068708109787484e-04 -8.5663070212203200e-04  2.1302563179109169e-03
+   29 -2.5054744388303732e-03 -1.6773997805290820e-04  2.8436699761004796e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-nve.yaml
+++ b/unittest/force-styles/tests/fix-timestep-nve.yaml
@ -0,0 +1,73 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 07:12:15 202
+epsilon: 1e-14
+prerequisites: ! |
+  atom full
+  fix nve
+pre_commands: ! ""
+post_commands: ! |
+  fix test solute nve
+input_file: in.fourmol
+natoms: 29
+run_pos: ! |2
+    1 -2.7045559764772636e-01  2.4912159908661540e+00 -1.6695851750890131e-01
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+   29 -1.3108232656499081e+00 -3.5992986322410760e+00  2.2680459788743503e+00
+run_vel: ! |2
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+   24  2.5447450568861086e-04  4.8412447786110117e-04 -4.8021914527341357e-04
+   25  4.3722771097312743e-03 -4.5184411669545515e-03  2.5200952006556795e-03
+   26 -1.9250110555001179e-03 -3.0342169883610837e-03  3.5062814567984532e-03
+   27 -2.6510179146429716e-04  3.6306203629019116e-04 -5.6235585400647747e-04
+   28 -2.3068708109787484e-04 -8.5663070212203200e-04  2.1302563179109169e-03
+   29 -2.5054744388303732e-03 -1.6773997805290820e-04  2.8436699761004796e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-nvt.yaml
+++ b/unittest/force-styles/tests/fix-timestep-nvt.yaml
@ -0,0 +1,76 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 07:12:15 202
+epsilon: 5e-14
+prerequisites: ! |
+  atom full
+  fix nvt
+pre_commands: ! ""
+post_commands: ! |
+  fix test solute nvt temp 50.0 ${t_target} 1.0 mtk no tchain 1
+input_file: in.fourmol
+natoms: 29
+global_scalar: 161.082193606418
+global_vector: ! |-
+  4 6.3653490700601365 4.587389017747112 60.7164687353389 100.36572487107922
+run_pos: ! |2
+    1 -2.7696909697757566e-01  2.4783666916735787e+00 -1.7050542371974803e-01
+    2  3.0475247358534557e-01  2.9550852133930978e+00 -8.5567914575251569e-01
+    3 -6.9739816438327773e-01  1.2400856795511155e+00 -6.2409863799710530e-01
+    4 -1.5786703850642763e+00  1.4890498729340644e+00 -1.2508581595004804e+00
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+    6  2.7994521821983220e-01  2.4474061566700642e-01 -1.2668688023898995e+00
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+   17  2.2261096224365753e+00 -2.0982906145850206e+00  1.1642076197266931e+00
+   18  2.1384791188033843e+00  3.0177261773770208e+00 -3.5160827596876225e+00
+   19  1.5349125211132961e+00  2.6315969880333707e+00 -4.2472859440220647e+00
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+run_vel: ! |2
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+   24  2.5447450568861086e-04  4.8412447786110117e-04 -4.8021914527341357e-04
+   25  4.3722771097312743e-03 -4.5184411669545515e-03  2.5200952006556795e-03
+   26 -1.9250110555001179e-03 -3.0342169883610837e-03  3.5062814567984532e-03
+   27 -2.6510179146429716e-04  3.6306203629019116e-04 -5.6235585400647747e-04
+   28 -2.3068708109787484e-04 -8.5663070212203200e-04  2.1302563179109169e-03
+   29 -2.5054744388303732e-03 -1.6773997805290820e-04  2.8436699761004796e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-press_berendsen_iso.yaml
+++ b/unittest/force-styles/tests/fix-timestep-press_berendsen_iso.yaml
@ -0,0 +1,74 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 16:44:09 202
+epsilon: 2e-13
+prerequisites: ! |
+  atom full
+  fix press/berendsen
+pre_commands: ! ""
+post_commands: ! |
+  fix all solute nve
+  fix test solute press/berendsen iso 5000.0 5000.0 10000.0
+input_file: in.fourmol
+natoms: 29
+run_pos: ! |2
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+   29 -2.5054744388303732e-03 -1.6773997805290820e-04  2.8436699761004796e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-rattle_angle.yaml
+++ b/unittest/force-styles/tests/fix-timestep-rattle_angle.yaml
@ -0,0 +1,77 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 16:30:21 202
+epsilon: 2e-13
+prerequisites: ! |
+  atom full
+  fix rattle
+pre_commands: ! ""
+post_commands: ! |
+  fix move all nve
+  fix test solvent rattle 1.0e-5 20 4 b 5 a 1
+  fix_modify test virial yes
+input_file: in.fourmol
+natoms: 29
+run_stress: ! |-
+  -6.7489444076122581e+01 -3.6466857275816793e+01 -4.1453650662488030e+01 -3.0881715538687999e+01 -2.8271646386126275e+01  1.8512924155867125e-01
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+   29  6.4110631474916110e-04  3.1273432713407900e-03  3.7253671102111473e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-rattle_bond.yaml
+++ b/unittest/force-styles/tests/fix-timestep-rattle_bond.yaml
@ -0,0 +1,77 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 16:30:21 202
+epsilon: 2e-13
+prerequisites: ! |
+  atom full
+  fix rattle
+pre_commands: ! ""
+post_commands: ! |
+  fix move all nve
+  fix test solute rattle 1.0e-5 20 4 m 4.00794
+  fix_modify test virial yes
+input_file: in.fourmol
+natoms: 29
+run_stress: ! |2-
+   3.9891557115890999e+00  3.7983351717152480e+00  7.6152694943743228e+01  5.7163462651523300e-01  3.0839737670745507e+01  3.0066936263232019e+01
+run_pos: ! |2
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+   29  6.4110628696208052e-04  3.1273432221612541e-03  3.7253671295737062e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-rigid-group.yaml
+++ b/unittest/force-styles/tests/fix-timestep-rigid-group.yaml
@ -0,0 +1,78 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 16:30:21 202
+epsilon: 2.5e-13
+prerequisites: ! |
+  atom full
+  fix rigid
+pre_commands: ! ""
+post_commands: ! |
+  variable t_target delete
+  fix test all rigid group 2 solute solvent
+  fix_modify test virial yes
+input_file: in.fourmol
+natoms: 29
+run_stress: ! |-
+  -1.4245356937318927e+03 -1.4496493315649675e+03 -3.6144360984224963e+03  8.4840626828643849e+02  2.0318336761611764e+02 -6.0622397707969685e+02
+global_scalar: 15.7115214231781
+run_pos: ! |2
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+   29 -2.5054744388303732e-03 -1.6773997805290820e-04  2.8436699761004796e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-rigid-molecule.yaml
+++ b/unittest/force-styles/tests/fix-timestep-rigid-molecule.yaml
@ -0,0 +1,78 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 16:30:21 202
+epsilon: 2.5e-13
+prerequisites: ! |
+  atom full
+  fix rigid
+pre_commands: ! ""
+post_commands: ! |
+  variable t_target delete
+  fix test solvent rigid molecule
+  fix_modify test virial yes
+input_file: in.fourmol
+natoms: 29
+run_stress: ! |-
+  -4.9200116134790363e+01 -2.6907707565987732e+01 -6.0080860422282560e+00 -2.5620423972101747e+01 -1.3450224059984075e+01 -1.4947288487004844e+00
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+   29 -2.5054744388303732e-03 -1.6773997805290820e-04  2.8436699761004796e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-rigid-single.yaml
+++ b/unittest/force-styles/tests/fix-timestep-rigid-single.yaml
@ -0,0 +1,78 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 16:30:21 202
+epsilon: 2.5e-13
+prerequisites: ! |
+  atom full
+  fix rigid
+pre_commands: ! ""
+post_commands: ! |
+  variable t_target delete
+  fix test solute rigid single
+  fix_modify test virial yes
+input_file: in.fourmol
+natoms: 29
+run_stress: ! |-
+  -1.3754817466835852e+03 -1.4228425246165939e+03 -3.6087196201913630e+03  8.7407043149698166e+02  2.1665316519768876e+02 -6.0480791462031175e+02
+global_scalar: 4.53142303857031
+run_pos: ! |2
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+   29 -2.5054744388303732e-03 -1.6773997805290820e-04  2.8436699761004796e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-setforce-const.yaml
+++ b/unittest/force-styles/tests/fix-timestep-setforce-const.yaml
@ -0,0 +1,76 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 07:12:16 202
+epsilon: 2e-13
+prerequisites: ! |
+  atom full
+  fix setforce
+pre_commands: ! ""
+post_commands: ! |
+  fix move all nve
+  fix test solute setforce 0.0 NULL 0.1
+input_file: in.fourmol
+natoms: 29
+global_vector: ! |-
+  3 0.031196595768662405 0.027176378299685666 -0.018248127488959653
+run_pos: ! |2
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+   29  6.4110655335636812e-04  3.1273431604200374e-03  3.7253670254479500e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-setforce-region.yaml
+++ b/unittest/force-styles/tests/fix-timestep-setforce-region.yaml
@ -0,0 +1,77 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 15:15:21 202
+epsilon: 2e-13
+prerequisites: ! |
+  atom full
+  fix setforce
+pre_commands: ! ""
+post_commands: ! |
+  region half block 0 EDGE EDGE EDGE EDGE EDGE
+  fix move all nve
+  fix test solute setforce 0.0 0.0 0.0 region half
+input_file: in.fourmol
+natoms: 29
+global_vector: ! |-
+  3 30.2599905309868 33.68278530642225 -29.246531241430393
+run_pos: ! |2
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+   26  2.0485904659168050e-03  2.7813359700824256e-03  4.3245727588882886e-03
+   27  4.5604046194129701e-04 -1.0305531094668544e-03  2.1187977265303768e-04
+   28 -6.2544520782408771e-03  1.4127711142458772e-03 -1.8429822149784341e-03
+   29  6.4110649875996400e-04  3.1273432160629365e-03  3.7253670337420121e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-setforce-variable.yaml
+++ b/unittest/force-styles/tests/fix-timestep-setforce-variable.yaml
@ -0,0 +1,81 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 07:31:40 202
+epsilon: 2e-13
+prerequisites: ! |
+  atom full
+  fix setforce
+pre_commands: ! ""
+post_commands: ! |
+  fix init all store/state 0 x y z
+  variable xforce delete
+  variable xforce atom f_init[1]
+  variable zforce delete
+  variable zforce equal 0.1*step/10.0
+  fix move all nve
+  fix test solute setforce v_xforce NULL v_zforce
+input_file: in.fourmol
+natoms: 29
+global_vector: ! |-
+  3 0.031197043446070438 0.027174896355546707 -0.0182497728803952
+run_pos: ! |2
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+    2  3.0745979269788315e-01  2.9612799003321073e+00 -8.4973076516933943e-01
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+run_vel: ! |2
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+   25  1.3789867459853888e-04 -4.4335884646610046e-03 -8.1807894538992332e-04
+   26  2.0485905361409002e-03  2.7813360188135763e-03  4.3245728523802927e-03
+   27  4.5604012089853278e-04 -1.0305533883296402e-03  2.1187985225197545e-04
+   28 -6.2544520817733613e-03  1.4127710886673889e-03 -1.8429822030169415e-03
+   29  6.4110655177640171e-04  3.1273431592077948e-03  3.7253670266864263e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-shake_angle.yaml
+++ b/unittest/force-styles/tests/fix-timestep-shake_angle.yaml
@ -0,0 +1,77 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 16:30:22 202
+epsilon: 2e-12
+prerequisites: ! |
+  atom full
+  fix shake
+pre_commands: ! ""
+post_commands: ! |
+  fix move all nve
+  fix test solvent shake 1.0e-5 20 4 b 5 a 1
+  fix_modify test virial yes
+input_file: in.fourmol
+natoms: 29
+run_stress: ! |-
+  -6.7489461181454146e+01 -3.6466852749734755e+01 -4.1453635345326461e+01 -3.0881721833345594e+01 -2.8271651455044346e+01  1.8512237607314627e-01
+run_pos: ! |2
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+   29  6.4110631474916110e-04  3.1273432713407900e-03  3.7253671102111473e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-shake_bond.yaml
+++ b/unittest/force-styles/tests/fix-timestep-shake_bond.yaml
@ -0,0 +1,77 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 16:30:22 202
+epsilon: 2e-12
+prerequisites: ! |
+  atom full
+  fix shake
+pre_commands: ! ""
+post_commands: ! |
+  fix move all nve
+  fix test solute shake 1.0e-5 20 4 m 4.00794
+  fix_modify test virial yes
+input_file: in.fourmol
+natoms: 29
+run_stress: ! |2-
+   4.1327164284089424e+00  4.1298776885725212e+00  7.7065049821613400e+01  7.3427739401911385e-01  3.1021321349896283e+01  3.0482918118325731e+01
+run_pos: ! |2
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+   29 -1.3126000191565619e+00 -3.5962518039874860e+00  2.2746342468906682e+00
+run_vel: ! |2
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+   25  1.3789825021844792e-04 -4.4335889596263511e-03 -8.1808100227326449e-04
+   26  2.0485904735292599e-03  2.7813359659683385e-03  4.3245727170611618e-03
+   27  4.5604110580961207e-04 -1.0305524671180935e-03  2.1188063421234097e-04
+   28 -6.2544520944132998e-03  1.4127711036803850e-03 -1.8429821866102578e-03
+   29  6.4110628696208052e-04  3.1273432221612541e-03  3.7253671295737062e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-temp_berendsen.yaml
+++ b/unittest/force-styles/tests/fix-timestep-temp_berendsen.yaml
@ -0,0 +1,75 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 07:12:16 202
+epsilon: 1e-14
+prerequisites: ! |
+  atom full
+  fix temp/berendsen
+pre_commands: ! ""
+post_commands: ! |
+  fix all solute nve
+  fix test solute temp/berendsen 50.0 ${t_target} 1.0
+input_file: in.fourmol
+natoms: 29
+global_scalar: 140.500399901528
+run_pos: ! |2
+    1 -2.7309636642471763e-01  2.4861645745691683e+00 -1.6828848361402490e-01
+    2  3.0754156828804369e-01  2.9580811430810168e+00 -8.5566344544442696e-01
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+   29 -1.3108232656499081e+00 -3.5992986322410760e+00  2.2680459788743503e+00
+run_vel: ! |2
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+   23  2.4209481134686401e-04 -4.5457709985051130e-03  2.7663581642115042e-03
+   24  2.5447450568861086e-04  4.8412447786110117e-04 -4.8021914527341357e-04
+   25  4.3722771097312743e-03 -4.5184411669545515e-03  2.5200952006556795e-03
+   26 -1.9250110555001179e-03 -3.0342169883610837e-03  3.5062814567984532e-03
+   27 -2.6510179146429716e-04  3.6306203629019116e-04 -5.6235585400647747e-04
+   28 -2.3068708109787484e-04 -8.5663070212203200e-04  2.1302563179109169e-03
+   29 -2.5054744388303732e-03 -1.6773997805290820e-04  2.8436699761004796e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-temp_csld.yaml
+++ b/unittest/force-styles/tests/fix-timestep-temp_csld.yaml
@ -0,0 +1,75 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 14:54:04 202
+epsilon: 1e-14
+prerequisites: ! |
+  atom full
+  fix temp/csld
+pre_commands: ! ""
+post_commands: ! |
+  fix all solute nve
+  fix test solute temp/csld 50.0 ${t_target} 1.0 62823
+input_file: in.fourmol
+natoms: 29
+global_scalar: 150.876840894722
+run_pos: ! |2
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+   11  1.7825785169979784e+00 -1.9874255508702292e+00 -1.8881581493841835e+00
+   12  3.0057154639626575e+00 -4.9097688194559375e-01 -1.6180318028907086e+00
+   13  4.0485629820926592e+00 -8.9431038872519708e-01 -1.6345003838044976e+00
+   14  2.6060153448114884e+00 -4.1286533645721485e-01 -2.6584607156586810e+00
+   15  2.9703775066451663e+00  5.6063984758286523e-01 -1.2411803092256180e+00
+   16  2.6656970686950041e+00 -2.4008304027486727e+00  2.4324587822466010e-04
+   17  2.2170696923898499e+00 -2.0966249045214056e+00  1.1748374924569560e+00
+   18  2.1384791188033843e+00  3.0177261773770208e+00 -3.5160827596876225e+00
+   19  1.5349125211132961e+00  2.6315969880333707e+00 -4.2472859440220647e+00
+   20  2.7641167828863153e+00  3.6833419064000221e+00 -3.9380850623312638e+00
+   21  4.9064454390208301e+00 -4.0751205255383196e+00 -3.6215576073601046e+00
+   22  4.3687453488627543e+00 -4.2054270536772504e+00 -4.4651491269372565e+00
+   23  5.7374928154769504e+00 -3.5763355905184966e+00 -3.8820297194230728e+00
+   24  2.0684115301174013e+00  3.1518221747664397e+00  3.1554242678474576e+00
+   25  1.2998381073113014e+00  3.2755513587518097e+00  2.5092990173114837e+00
+   26  2.5807438597688113e+00  4.0120175892854135e+00  3.2133398379059099e+00
+   27 -1.9613581876744359e+00 -4.3556300596085160e+00  2.1101467673534788e+00
+   28 -2.7406520384725965e+00 -4.0207251278130975e+00  1.5828689861678511e+00
+   29 -1.3108232656499081e+00 -3.5992986322410760e+00  2.2680459788743503e+00
+run_vel: ! |2
+    1 -6.1518106640055098e-04  9.8413236728091859e-03  2.6821401423517848e-03
+    2  5.7584895033439311e-03 -6.4512016069715183e-03 -4.6331491821159322e-03
+    3 -4.3045744902141230e-03 -1.1357763612046034e-03 -1.5278167433944827e-03
+    4 -7.9024210036195315e-04  8.4724079430485693e-03  8.7245281838652239e-03
+    5  2.7579652970089745e-03 -5.9025323603549475e-04 -2.5454023443268127e-03
+    6 -1.4815311727055615e-02  2.0221004909579707e-02  1.5396636244631938e-02
+    7  6.3241608228865333e-04 -1.0634159681637320e-03 -1.6769555657594071e-02
+    8  1.5893486075269094e-03 -6.1660323394415405e-04  1.3789272460195160e-02
+    9  7.4801357958314968e-03 -1.7324571377721242e-04  5.5874995558103397e-03
+   10  1.3183178250648638e-02 -7.4440255996034814e-03 -1.4024578089719738e-03
+   11 -3.6967525507180790e-03 -7.9577777641821126e-03 -2.0130547563199353e-03
+   12  1.7809421251718035e-03 -2.4228240354331847e-04 -2.9652050547483645e-03
+   13  4.3878889923020296e-04  3.8672876750012147e-03 -6.6580707926174529e-03
+   14 -5.2616323633526024e-04 -4.5860320088099964e-03  5.2733721735657773e-04
+   15 -2.1083712534527002e-03  2.9658835298400901e-03  9.1125829125389391e-04
+   16  6.3044701073886288e-03 -1.5176887611785819e-03 -1.7062686137992850e-02
+   17 -8.3474333369752789e-03  1.5146606349005583e-03  1.4823067912505096e-02
+   18 -6.0936815808025862e-04 -9.3774557532468582e-04 -3.3558072507805731e-04
+   19 -6.9919768291957119e-04 -3.6060777270430031e-03  4.2833405289822791e-03
+   20  4.7777805013736515e-03  5.1003745845520452e-03  1.8002873923729241e-03
+   21 -9.5568188553430398e-04  1.6594630943762931e-04 -1.8199788009966615e-04
+   22 -3.3137518957653462e-03 -2.8683968287936054e-03  3.6384389958326871e-03
+   23  2.4209481134686401e-04 -4.5457709985051130e-03  2.7663581642115042e-03
+   24  2.5447450568861086e-04  4.8412447786110117e-04 -4.8021914527341357e-04
+   25  4.3722771097312743e-03 -4.5184411669545515e-03  2.5200952006556795e-03
+   26 -1.9250110555001179e-03 -3.0342169883610837e-03  3.5062814567984532e-03
+   27 -2.6510179146429716e-04  3.6306203629019116e-04 -5.6235585400647747e-04
+   28 -2.3068708109787484e-04 -8.5663070212203200e-04  2.1302563179109169e-03
+   29 -2.5054744388303732e-03 -1.6773997805290820e-04  2.8436699761004796e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-temp_csvr.yaml
+++ b/unittest/force-styles/tests/fix-timestep-temp_csvr.yaml
@ -0,0 +1,75 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 14:53:58 202
+epsilon: 1e-14
+prerequisites: ! |
+  atom full
+  fix temp/csvr
+pre_commands: ! ""
+post_commands: ! |
+  fix all solute nve
+  fix test solute temp/csvr 50.0 ${t_target} 1.0 82573
+input_file: in.fourmol
+natoms: 29
+global_scalar: 138.691817964765
+run_pos: ! |2
+    1 -2.7280762260987462e-01  2.4866672893615482e+00 -1.6817690082511103e-01
+    2  3.0792532339926826e-01  2.9586317848907591e+00 -8.5537067987838589e-01
+    3 -7.0155509000995808e-01  1.2337201042383152e+00 -6.2645947625508680e-01
+    4 -1.5806259405926315e+00  1.4857183624992281e+00 -1.2524138927067634e+00
+    5 -9.0413749520933206e-01  9.2874389205720931e-01  4.0021691625350447e-01
+    6  2.5940135491607696e-01  2.6955443838876736e-01 -1.2440989174242931e+00
+    7  3.4115709633311569e-01 -1.9361196729511615e-02 -2.5133202867901732e+00
+    8  1.1718886190395006e+00 -4.8742160677430901e-01 -6.4725283909309406e-01
+    9  1.3794054639593258e+00 -2.5286053024356114e-01  2.7978731678256097e-01
+   10  2.0431332821795114e+00 -1.4526503498146288e+00 -9.7932641944253374e-01
+   11  1.7890934771379468e+00 -1.9908605501813910e+00 -1.8876922594986423e+00
+   12  3.0054411287235951e+00 -4.8987634219780540e-01 -1.6220627513203476e+00
+   13  4.0496794476606635e+00 -8.9447232940528654e-01 -1.6395816350351760e+00
+   14  2.6058661355197810e+00 -4.1525413418121015e-01 -2.6612700962724607e+00
+   15  2.9712318526989474e+00  5.5661112285831083e-01 -1.2366977651516922e+00
+   16  2.6691735451973395e+00 -2.4083535475815920e+00 -9.9660994024412010e-03
+   17  2.2190855332677919e+00 -2.0928268444165918e+00  1.1849187762465219e+00
+   18  2.1384791188033843e+00  3.0177261773770208e+00 -3.5160827596876225e+00
+   19  1.5349125211132961e+00  2.6315969880333707e+00 -4.2472859440220647e+00
+   20  2.7641167828863153e+00  3.6833419064000221e+00 -3.9380850623312638e+00
+   21  4.9064454390208301e+00 -4.0751205255383196e+00 -3.6215576073601046e+00
+   22  4.3687453488627543e+00 -4.2054270536772504e+00 -4.4651491269372565e+00
+   23  5.7374928154769504e+00 -3.5763355905184966e+00 -3.8820297194230728e+00
+   24  2.0684115301174013e+00  3.1518221747664397e+00  3.1554242678474576e+00
+   25  1.2998381073113014e+00  3.2755513587518097e+00  2.5092990173114837e+00
+   26  2.5807438597688113e+00  4.0120175892854135e+00  3.2133398379059099e+00
+   27 -1.9613581876744359e+00 -4.3556300596085160e+00  2.1101467673534788e+00
+   28 -2.7406520384725965e+00 -4.0207251278130975e+00  1.5828689861678511e+00
+   29 -1.3108232656499081e+00 -3.5992986322410760e+00  2.2680459788743503e+00
+run_vel: ! |2
+    1  4.6937564710920216e-03  9.6555961564013804e-03  2.8708039254905881e-03
+    2  2.7267170444366185e-03  2.2058192686523290e-03 -1.5353913821082035e-03
+    3 -4.6306766915023894e-03 -7.9351414155915453e-03 -2.3497227140117419e-03
+    4 -2.0674867361574730e-03 -3.6722365151599765e-03  1.1155363952115448e-04
+    5 -6.3227892412089171e-03 -6.0246930339812061e-03 -1.6991048796308555e-03
+    6 -2.3313325205229000e-02  2.7197550589909671e-02  2.0738710039103190e-02
+    7  5.6010701530313550e-04 -5.7071338016654654e-03 -2.9476037762661333e-02
+    8  4.5357117797050145e-03 -1.7956042409071231e-03  2.0337353845153724e-02
+    9  6.9780844880996972e-04  2.7260623247486841e-03  8.7428367624614034e-03
+   10  1.7158823348639104e-02 -1.7353191765645898e-02 -8.8565471428928583e-03
+   11 -2.7754554284794915e-03 -1.9484853125617634e-03 -8.5708629159661183e-04
+   12  1.1446489442763310e-03 -8.1052477490650056e-05 -1.5736644561053304e-03
+   13  8.6708264237769490e-04  2.7906792431300104e-03 -3.2527835321513224e-04
+   14  2.1170915886558860e-03 -2.6750828934791800e-03 -1.6081787775879092e-03
+   15 -2.7969721465264459e-04 -2.8792217329085164e-03  3.1381108795769806e-03
+   16  1.0810115663068724e-02 -7.5713924362591457e-03 -2.6575629458356204e-02
+   17 -7.5547245737932044e-03  5.5628964952133871e-03  2.1384064341807719e-02
+   18 -6.0936815808025862e-04 -9.3774557532468582e-04 -3.3558072507805731e-04
+   19 -6.9919768291957119e-04 -3.6060777270430031e-03  4.2833405289822791e-03
+   20  4.7777805013736515e-03  5.1003745845520452e-03  1.8002873923729241e-03
+   21 -9.5568188553430398e-04  1.6594630943762931e-04 -1.8199788009966615e-04
+   22 -3.3137518957653462e-03 -2.8683968287936054e-03  3.6384389958326871e-03
+   23  2.4209481134686401e-04 -4.5457709985051130e-03  2.7663581642115042e-03
+   24  2.5447450568861086e-04  4.8412447786110117e-04 -4.8021914527341357e-04
+   25  4.3722771097312743e-03 -4.5184411669545515e-03  2.5200952006556795e-03
+   26 -1.9250110555001179e-03 -3.0342169883610837e-03  3.5062814567984532e-03
+   27 -2.6510179146429716e-04  3.6306203629019116e-04 -5.6235585400647747e-04
+   28 -2.3068708109787484e-04 -8.5663070212203200e-04  2.1302563179109169e-03
+   29 -2.5054744388303732e-03 -1.6773997805290820e-04  2.8436699761004796e-03
+...
--- a/unittest/force-styles/tests/fix-timestep-wall-harmonic_const.yaml
+++ b/unittest/force-styles/tests/fix-timestep-wall-harmonic_const.yaml
@ -0,0 +1,81 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Sun Aug  9 16:30:22 202
+epsilon: 1e-14
+prerequisites: ! |
+  atom full
+  fix wall/harmonic
+pre_commands: ! |
+  boundary p f p
+post_commands: ! |
+  fix move all nve
+  fix test solute wall/harmonic ylo EDGE 100.0 0.0 5.0 yhi EDGE 100.0 0.0 5.0
+  fix_modify test virial yes
+input_file: in.fourmol
+natoms: 29
+run_stress: ! |2-
+   0.0000000000000000e+00  7.2422093200265749e+02  0.0000000000000000e+00  0.0000000000000000e+00  0.0000000000000000e+00  0.0000000000000000e+00
+global_scalar: 42.6997744353244
+global_vector: ! |-
+  2 0.0 161.92409617466126
+run_pos: ! |2
+    1 -2.7051715090682593e-01  2.4891718422041942e+00 -1.6687343912524535e-01
+    2  3.1037661579862175e-01  2.9347166386691113e+00 -8.5496435221221156e-01
+    3 -7.0402515865264603e-01  1.2304739304383521e+00 -6.2777422080240730e-01
+    4 -1.5818156002522876e+00  1.4837443919066966e+00 -1.2538703954644463e+00
+    5 -9.0719963033698159e-01  9.2651871779341399e-01  3.9954137559444142e-01
+    6  2.4831695467823400e-01  2.8312974957866005e-01 -1.2314232372542311e+00
+    7  3.4143527599853957e-01 -2.2646552136496162e-02 -2.5292291409504188e+00
+    8  1.1743552256787158e+00 -4.8863229191571117e-01 -6.3783432834416876e-01
+    9  1.3800524227031346e+00 -2.5274721005121037e-01  2.8353985882456578e-01
+   10  2.0510765220197009e+00 -1.4604063740411815e+00 -9.8323745080488900e-01
+   11  1.7878031944407509e+00 -1.9921863272886073e+00 -1.8890602447598965e+00
+   12  3.0063007038317027e+00 -4.9013350489718083e-01 -1.6231898106978369e+00
+   13  4.0515402959160571e+00 -8.9202011606485654e-01 -1.6400005529914481e+00
+   14  2.6066963345462244e+00 -4.1789253964874301e-01 -2.6634003608727506e+00
+   15  2.9695287185264685e+00  5.5422613167055734e-01 -1.2342022021669503e+00
+   16  2.6747029695037297e+00 -2.4124119054292041e+00 -2.3435746152831474e-02
+   17  2.2153577785010934e+00 -2.0897985186506944e+00  1.1963150794337314e+00
+   18  2.1369701704267587e+00  3.0158507413153752e+00 -3.5179348337454122e+00
+   19  1.5355837136075348e+00  2.6255292355297897e+00 -4.2353987779858038e+00
+   20  2.7727573003201997e+00  3.6923910440705336e+00 -3.9330842459619779e+00
+   21  4.9040128073837339e+00 -4.0752348170758461e+00 -3.6210314709795299e+00
+   22  4.3582355554510048e+00 -4.2126119427061379e+00 -4.4612844196307497e+00
+   23  5.7439382849366911e+00 -3.5821957939240279e+00 -3.8766361295959513e+00
+   24  2.0689243582618388e+00  3.1513346906720905e+00  3.1550389755134005e+00
+   25  1.3045351331892774e+00  3.2665125705550957e+00  2.5111855258151388e+00
+   26  2.5809237402747862e+00  4.0117602605470681e+00  3.2212060529139430e+00
+   27 -1.9611343130344261e+00 -4.3563411931314180e+00  2.1098293115505782e+00
+   28 -2.7473562684511403e+00 -4.0200819932374339e+00  1.5830052163432258e+00
+   29 -1.3126000191357743e+00 -3.5962518039473323e+00  2.2746342468733483e+00
+run_vel: ! |2
+    1  8.0432349631399738e-03  1.4401841389211066e-02  4.9594370365889035e-03
+    2  6.1330361195047721e-03 -2.0880295268721646e-02 -2.0467529305087974e-03
+    3 -8.3074380171099336e-03 -1.3074180712034022e-02 -4.0925567431707964e-03
+    4 -3.7694367867060308e-03 -6.5650784618522641e-03 -1.1170951231990066e-03
+    5 -1.1026343955717482e-02 -9.8958287307442903e-03 -2.8423479505575383e-03
+    6 -3.9677127674597606e-02  4.6816039080495052e-02  3.7148638820894170e-02
+    7  9.1033730239907995e-04 -1.0128528243740664e-02 -5.1568250829251872e-02
+    8  7.9064772413549398e-03 -3.3507427942055237e-03  3.4557101116794005e-02
+    9  1.5644169779778431e-03  3.7365552198096001e-03  1.5047408727814703e-02
+   10  2.9201446825927659e-02 -2.9249578944835358e-02 -1.5018077412006621e-02
+   11 -4.7835961594766378e-03 -3.7481385002840358e-03 -2.3464104088049835e-03
+   12  2.2696449755579802e-03 -3.4774139663753471e-04 -3.0640769495163694e-03
+   13  2.7531740375147762e-03  5.8171061651960156e-03 -7.9467453772152246e-04
+   14  3.5246182201851949e-03 -5.7939995452846345e-03 -3.9478431035191433e-03
+   15 -1.8547944555517618e-03 -5.8554729566882438e-03  6.2938485388423782e-03
+   16  1.8681499934669346e-02 -1.3262466149576241e-02 -4.5638651461858082e-02
+   17 -1.2896270037715951e-02  9.7527666092669871e-03  3.7296535331498307e-02
+   18 -8.0065791408039360e-04 -8.6270482947906340e-04 -1.4483041230016333e-03
+   19  1.2452390812060273e-03 -2.5061097279531165e-03  7.2998631045687349e-03
+   20  3.5930057934746205e-03  3.6938851526077707e-03  3.2322732077980764e-03
+   21 -1.4689219756964986e-03 -2.7352107824531023e-04  7.0581625180910238e-04
+   22 -7.0694199165145270e-03 -4.2577148692717476e-03  2.8079117911324980e-04
+   23  6.0446963236685126e-03 -1.4000131545098867e-03  2.5819754799379689e-03
+   24  3.1926371811980247e-04 -9.9445676110986795e-04  1.5000003249577247e-04
+   25  1.3789762510432095e-04 -4.4335895501596183e-03 -8.1808122106665057e-04
+   26  2.0485904106950122e-03  2.7813358601316666e-03  4.3245727251785618e-03
+   27  4.5604120562021776e-04 -1.0305522931718021e-03  2.1188058006115626e-04
+   28 -6.2544520854975879e-03  1.4127711193315995e-03 -1.8429821890767147e-03
+   29  6.4110631581209361e-04  3.1273432740202512e-03  3.7253671096581808e-03
+...
--- a/unittest/force-styles/tests/in.fourmol
+++ b/unittest/force-styles/tests/in.fourmol
@ -11,6 +11,7 @@ variable  bond_style      index zero
 variable  angle_style     index zero
 variable  dihedral_style  index zero
 variable  improper_style  index zero
+variable  t_target        index 100.0

 atom_style       full
 atom_modify      map array
--- a/unittest/force-styles/tests/manybody-pair-extep.yaml
+++ b/unittest/force-styles/tests/manybody-pair-extep.yaml
@ -0,0 +1,155 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Tue Aug 11 09:00:37 202
+epsilon: 5e-13
+prerequisites: ! |
+  pair extep
+pre_commands: ! |
+  variable newton_pair delete
+  variable newton_pair index on
+post_commands: ! ""
+input_file: in.manybody
+pair_style: extep
+pair_coeff: ! |
+  * * BN.extep B B B B N N N N
+extract: ! ""
+natoms: 64
+init_vdwl: -8.35953889724907
+init_coul: 0
+init_stress: ! |-
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+...
--- a/unittest/force-styles/tests/mol-pair-e3b.yaml
+++ b/unittest/force-styles/tests/mol-pair-e3b.yaml
@ -0,0 +1,103 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Tue Aug 11 08:52:27 202
+epsilon: 5e-14
+prerequisites: ! |
+  atom full
+  pair lj/cut/tip4p/cut
+  pair e3b
+pre_commands: ! |
+  variable newton_pair delete
+  variable newton_pair index on
+post_commands: ! |
+  pair_modify mix arithmetic
+input_file: in.fourmol
+pair_style: hybrid/overlay lj/cut/tip4p/cut 5 2 5 1 0.15 10.0 e3b 5
+pair_coeff: ! |
+  1 1 lj/cut/tip4p/cut 0.02 2.5 8
+  1 2 lj/cut/tip4p/cut 0.01 1.75 8
+  1 3 lj/cut/tip4p/cut 0.02 2.85 8
+  1 4 lj/cut/tip4p/cut 0.0173205 2.8 8
+  1 5 lj/cut/tip4p/cut 0.0173205 2.8 8
+  2 2 lj/cut/tip4p/cut 0.0 1 8
+  2 3 lj/cut/tip4p/cut 0.0 2.1 8
+  2 4 lj/cut/tip4p/cut 0.0 0.5 8
+  2 5 lj/cut/tip4p/cut 0.0 2.05 8
+  3 3 lj/cut/tip4p/cut 0.02 3.2 8
+  3 4 lj/cut/tip4p/cut 0.0173205 3.15 8
+  3 5 lj/cut/tip4p/cut 0.0173205 3.15 8
+  4 4 lj/cut/tip4p/cut 0.015 3.1 8
+  4 5 lj/cut/tip4p/cut 0.015 3.1 8
+  5 5 lj/cut/tip4p/cut 0.015 3.1 8
+  * * e3b preset 2015
+extract: ! ""
+natoms: 29
+init_vdwl: 584.671488129934
+init_coul: -128.977932168035
+init_stress: ! |2-
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+   19  2.1299064571460709e+00 -1.7007860994064594e+00  6.5142742813041359e+00
+   20 -3.2615898343840461e+00 -5.6090812774873386e+00  4.2429891063539174e+00
+   21  8.0741655650871391e-01  3.0937838483255220e+00 -7.2914969367797333e+00
+   22  3.9626151599754680e+00  1.5703953876725520e+00  4.8509806980792467e+00
+   23 -7.0701628159593684e+00 -4.4624515654731045e+00  2.0542173004071516e+00
+   24 -9.5064820343282552e-01  8.5254518575092533e+00 -5.0323755005400344e+00
+   25  5.5723194185180853e+00 -7.0640318784218714e-01  4.4527210593220081e+00
+   26 -4.8649543979323449e+00 -7.4562688050941262e+00 -1.0189293139994318e+00
+   27 -1.5562227560397666e+00  9.3814184738732589e+00 -3.7918644430887172e+00
+   28  8.9221127912602523e+00 -2.5727955175008117e+00  4.4191999926606860e+00
+   29 -3.6328666974943009e+00 -5.3344846333902503e+00 -1.6032273961495329e+00
+...
--- a/unittest/force-styles/tests/mol-pair-lj_expand_coul_long.yaml
+++ b/unittest/force-styles/tests/mol-pair-lj_expand_coul_long.yaml
@ -0,0 +1,99 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Tue Aug 11 08:37:39 202
+epsilon: 5e-14
+prerequisites: ! |
+  atom full
+  pair lj/expand/coul/long
+  kspace ewald
+pre_commands: ! ""
+post_commands: ! |
+  pair_modify mix arithmetic
+  pair_modify table 0
+  kspace_style ewald 1.0e-6
+  kspace_modify gewald 0.3
+  kspace_modify compute no
+input_file: in.fourmol
+pair_style: lj/expand/coul/long 8.0
+pair_coeff: ! |
+  1 1  0.02   2.0  0.2
+  2 2  0.005  0.9  0.05
+  2 4  0.005  0.5  0.0
+  3 3  0.02   3.0  0.1
+  4 4  0.015  2.8  0.2
+  5 5  0.015  3.0  0.1
+extract: ! |
+  epsilon 2
+  sigma 2
+  delta 2
+  cut_coul 0
+natoms: 29
+init_vdwl: 869.656344368552
+init_coul: 225.821815126925
+init_stress: ! |2-
+   2.5921580595929599e+03  2.4223089648929408e+03  6.9507399765892142e+03 -7.6459626076358222e+02 -1.7918244275053834e+02  1.1183600453689403e+03
+init_forces: ! |2
+    1 -4.7163194993221921e+01  2.2834247667596466e+02  3.4399687026134501e+02
+    2  1.7562443841600245e+02  1.4182973479795353e+02 -2.0831292146068489e+02
+    3 -1.2508615422916209e+02 -3.6798478249421532e+02 -1.3720477917795262e+02
+    4 -3.9145743460634925e+00  1.0488894945820071e+00 -2.9680205263326322e+00
+    5 -1.8403216196557828e+00 -1.4631790175600645e+00  6.0818528534738743e+00
+    6 -9.2216725524164417e+02  1.2287745546964902e+03  2.2653003222879815e+03
+    7  1.0275707795039158e+02 -5.6390694232542774e+02 -2.8553236422687523e+03
+    8  1.6813921559524184e+02 -1.4215967591199117e+02  3.8455917372053079e+02
+    9  9.1633373141575092e+01  9.1135118977716260e+01  3.9972970456422297e+02
+   10  5.5213457206939290e+02 -6.1976136814234292e+02 -1.8860732888734617e+02
+   11 -2.0653675404799192e+00 -1.9067213274695838e+00 -5.3629740928473808e+00
+   12  1.0622339756587413e+01  3.7670290663605148e+00 -1.8951373230563124e+00
+   13  3.7979473912697639e+00 -1.5435840347766145e+00 -2.4862388019885942e-01
+   14 -2.6935751635250607e+00  6.8698447653665595e-01 -4.3199669038668977e+00
+   15  2.5305893336076402e-01  3.8734449064195666e+00  4.3728299263740644e-01
+   16  7.2257309643596500e+02 -5.0816302107737170e+02 -1.9004596846603879e+03
+   17 -7.2145162953831516e+02  5.0721299277434184e+02  1.9029446585766536e+03
+   18  3.5593705560721056e-01  4.7720713300386546e+00 -7.8585034601445987e+00
+   19  1.9901810484621900e+00 -7.2114077843799396e-01  5.5216952988893828e+00
+   20 -2.9133092098729327e+00 -3.9873677744238525e+00  4.1253495034041823e+00
+   21 -1.0687319925822113e+02 -1.1890793959935895e+02  3.3030668807680365e+02
+   22 -1.6028118341131955e+02 -3.9850733869417056e+01 -2.4839117366825639e+02
+   23  2.6673946632604520e+02  1.5917281492245272e+02 -8.1412460602247450e+01
+   24  5.1622158551485391e+01 -3.1012002813557126e+02  1.6256339625935138e+02
+   25 -2.1901544438381163e+02  3.2814417155094908e+01 -1.8327904773796419e+02
+   26  1.6682970445882268e+02  2.7704983777814613e+02  2.0098819799158946e+01
+   27  7.8770042564417935e+01 -3.3142512544733739e+02  1.3455926026230580e+02
+   28 -2.6908794572326946e+02  1.1327040559793579e+02 -1.8145185065043862e+02
+   29  1.9071054496393484e+02  2.1815083728566805e+02  4.6871040843718049e+01
+run_vdwl: 106.16792769211
+run_coul: 232.783864793706
+run_stress: ! |2-
+   5.4033888248203050e+02  5.4892480012296539e+02  2.8955268865699099e+02 -3.1667993938546078e+02 -5.9418517757321624e+01  1.4135196526059173e+02
+run_forces: ! |2
+    1  1.5042193015751637e+01  7.0524187021246291e+01  5.3102809431837898e+01
+    2  1.6025096019454882e+01  1.0007003422930383e+01 -2.1158888230513998e+01
+    3 -2.9508462511221728e+02  1.5540065134595568e+02  1.0032166848378883e+02
+    4 -4.6990135745775357e+00  1.7664562746630565e+00 -3.4155588447655587e+00
+    5 -1.6647491427755032e+00 -7.1384505520861741e-01  5.6231908788594200e+00
+    6  1.9229113379974908e+02 -1.6879183079864617e+02 -1.5821197940587550e+02
+    7  1.3268776214088212e+00 -3.0212070504821389e+00 -1.3945917603050320e+01
+    8 -3.0767948041849035e+01  3.3774723064931294e+01  4.1455210291132609e+01
+    9  1.0981624610986977e+01  3.5815171517217190e+00  4.2835213459206827e+01
+   10  7.0651343131573768e+01 -7.5364530217274577e+01 -6.2700552936028060e+01
+   11 -4.6552674358648485e+00 -3.3640968147579642e+00 -1.0071392966729430e+01
+   12  9.6965594010440821e+00  4.5621471489456713e+00 -2.1188025874175360e+00
+   13  3.5106358717622150e+00 -1.2472767160147971e+00 -3.8580287143749975e-01
+   14 -2.8511582585326667e+00  6.3130353605272560e-01 -3.6224095602913993e+00
+   15 -2.5947961667870077e-02  3.6550638292073843e+00  4.1732465355119469e-01
+   16  3.1351531521993351e+01 -4.3039259230988741e+01  1.7506976000755010e+01
+   17 -9.2563379856300898e+00  1.1242483524947740e+01  1.2152716943210445e+01
+   18 -5.9670106666608946e-01  4.9523970836146356e+00 -6.4763569969688159e+00
+   19  2.3605537941351202e+00 -1.0192980643878549e+00  5.4296196146473630e+00
+   20 -2.7295307430735738e+00 -3.9126961062803156e+00  3.4455294221899790e+00
+   21 -6.6351053993518860e+00 -5.6936051291677838e+00  2.5340192737673494e+01
+   22 -1.2600719852052331e+01 -3.7030527797125199e+00 -1.9178428988156423e+01
+   23  1.8521698071959683e+01  1.0087220143578394e+01 -5.2549329175309047e+00
+   24  8.9245861393053083e+00 -2.1746250247417159e+01  1.5024118744729005e+01
+   25 -2.1454838578353829e+01  2.4698375849765086e+00 -1.7961262545369252e+01
+   26  1.1612405148647868e+01  1.8957323157416415e+01  1.9242901272291062e+00
+   27  8.6191024303209324e-02 -2.3639345894753781e+01  6.2652733477098339e+00
+   28 -1.5812874994926165e+01  6.0673559816231579e+00 -1.0405039947171305e+01
+   29  1.6452388975462700e+01  1.7576623833281324e+01  4.0631922647850391e+00
+...
--- a/unittest/force-styles/tests/mol-pair-lj_expand_coul_table.yaml
+++ b/unittest/force-styles/tests/mol-pair-lj_expand_coul_table.yaml
@ -0,0 +1,99 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Tue Aug 11 08:37:46 202
+epsilon: 2e-13
+prerequisites: ! |
+  atom full
+  pair lj/expand/coul/long
+  kspace ewald
+pre_commands: ! ""
+post_commands: ! |
+  pair_modify mix arithmetic
+  pair_modify table 16
+  kspace_style ewald 1.0e-6
+  kspace_modify gewald 0.3
+  kspace_modify compute no
+input_file: in.fourmol
+pair_style: lj/expand/coul/long 8.0
+pair_coeff: ! |
+  1 1  0.02   2.0  0.2
+  2 2  0.005  0.9  0.05
+  2 4  0.005  0.5  0.0
+  3 3  0.02   3.0  0.1
+  4 4  0.015  2.8  0.2
+  5 5  0.015  3.0  0.1
+extract: ! |
+  epsilon 2
+  sigma 2
+  delta 2
+  cut_coul 0
+natoms: 29
+init_vdwl: 869.656344368552
+init_coul: 225.821851347828
+init_stress: ! |2-
+   2.5921580798556824e+03  2.4223089706490100e+03  6.9507399900138435e+03 -7.6459625746898860e+02 -1.7918243325539206e+02  1.1183600494596001e+03
+init_forces: ! |2
+    1 -4.7163196497192146e+01  2.2834247625360311e+02  3.4399686846972884e+02
+    2  1.7562443791586878e+02  1.4182973406537658e+02 -2.0831292012253465e+02
+    3 -1.2508615412049755e+02 -3.6798478260953948e+02 -1.3720477930247748e+02
+    4 -3.9145743494796221e+00  1.0488899572714241e+00 -2.9680203360986748e+00
+    5 -1.8403214518471285e+00 -1.4631780700724715e+00  6.0818530886023696e+00
+    6 -9.2216725569750508e+02  1.2287745556395873e+03  2.2653003204922916e+03
+    7  1.0275707715277815e+02 -5.6390694237167190e+02 -2.8553236443303790e+03
+    8  1.6813921486566832e+02 -1.4215967617670751e+02  3.8455917576207537e+02
+    9  9.1633374940159385e+01  9.1135118386813176e+01  3.9972970646304736e+02
+   10  5.5213457218623114e+02 -6.1976136770574067e+02 -1.8860732949551110e+02
+   11 -2.0653676548734623e+00 -1.9067206261734890e+00 -5.3629739888026009e+00
+   12  1.0622339925344464e+01  3.7670291242792402e+00 -1.8951382266525523e+00
+   13  3.7979474711116428e+00 -1.5435841677028326e+00 -2.4862374988427219e-01
+   14 -2.6935753079358653e+00  6.8698435600643282e-01 -4.3199667618308677e+00
+   15  2.5305888243541896e-01  3.8734446145889341e+00  4.3728358791332234e-01
+   16  7.2257309763088028e+02 -5.0816302227466247e+02 -1.9004596843358918e+03
+   17 -7.2145162977104178e+02  5.0721299303460768e+02  1.9029446585142175e+03
+   18  3.5593760651461531e-01  4.7720712851654818e+00 -7.8585043264622421e+00
+   19  1.9901790463157074e+00 -7.2114219691675963e-01  5.5216951671183532e+00
+   20 -2.9133073882620311e+00 -3.9873665785059766e+00  4.1253505922291556e+00
+   21 -1.0687319963014248e+02 -1.1890793903453265e+02  3.3030668864705302e+02
+   22 -1.6028118611248254e+02 -3.9850735525595468e+01 -2.4839117530412136e+02
+   23  2.6673946951865724e+02  1.5917281609743972e+02 -8.1412459717501179e+01
+   24  5.1622158847869976e+01 -3.1012002774355045e+02  1.6256339581267164e+02
+   25 -2.1901544635946527e+02  3.2814415857796341e+01 -1.8327904858335660e+02
+   26  1.6682970674933870e+02  2.7704983923248733e+02  2.0098821433126425e+01
+   27  7.8770042449054543e+01 -3.3142512528162013e+02  1.3455926006838362e+02
+   28 -2.6908794843481189e+02  1.1327040466303316e+02 -1.8145185186649925e+02
+   29  1.9071054758730884e+02  2.1815083779493665e+02  4.6871042349543053e+01
+run_vdwl: 106.167927306934
+run_coul: 232.783872560844
+run_stress: ! |2-
+   5.4033889185122246e+02  5.4892479679809765e+02  2.8955268188032755e+02 -3.1667993134714584e+02 -5.9418514448016722e+01  1.4135196542323126e+02
+run_forces: ! |2
+    1  1.5042191731528032e+01  7.0524187035940841e+01  5.3102809100251832e+01
+    2  1.6025095744488677e+01  1.0007002564822953e+01 -2.1158887488756886e+01
+    3 -2.9508462401688416e+02  1.5540064992154834e+02  1.0032166792537170e+02
+    4 -4.6990139078806985e+00  1.7664569920998929e+00 -3.4155586861921678e+00
+    5 -1.6647490390909379e+00 -7.1384403123709927e-01  5.6231913002355691e+00
+    6  1.9229113649576860e+02 -1.6879183322567181e+02 -1.5821198229106906e+02
+    7  1.3268779483228397e+00 -3.0212055830968931e+00 -1.3945914850434395e+01
+    8 -3.0767951196938704e+01  3.3774724457681103e+01  4.1455210935792906e+01
+    9  1.0981625491800322e+01  3.5815167138957573e+00  4.2835213672255946e+01
+   10  7.0651342880628548e+01 -7.5364529395568468e+01 -6.2700552629269403e+01
+   11 -4.6552675714512306e+00 -3.3640962703239836e+00 -1.0071392993905647e+01
+   12  9.6965597982755973e+00  4.5621468027776313e+00 -2.1188034676686951e+00
+   13  3.5106360312289651e+00 -1.2472769016775080e+00 -3.8580273777294372e-01
+   14 -2.8511586869301606e+00  6.3130344465834132e-01 -3.6224094710691888e+00
+   15 -2.5948083380200986e-02  3.6550635613088232e+00  4.1732526656150110e-01
+   16  3.1351530288856495e+01 -4.3039257792019207e+01  1.7506979549615181e+01
+   17 -9.2563361597161808e+00  1.1242483077205343e+01  1.2152712647114377e+01
+   18 -5.9670063451193034e-01  4.9523968092195076e+00 -6.4763579876532082e+00
+   19  2.3605517380981142e+00 -1.0192995004118002e+00  5.4296195197490729e+00
+   20 -2.7295289246110710e+00 -3.9126947888476593e+00  3.4455303030875251e+00
+   21 -6.6351057460657072e+00 -5.6936042652828442e+00  2.5340192741066605e+01
+   22 -1.2600721158161978e+01 -3.7030538274119085e+00 -1.9178429616278798e+01
+   23  1.8521699843022176e+01  1.0087220490406569e+01 -5.2549324889294233e+00
+   24  8.9245858291795237e+00 -2.1746249717816461e+01  1.5024117239152851e+01
+   25 -2.1454839054527017e+01  2.4698362443277517e+00 -1.7961262718374137e+01
+   26  1.1612406206864165e+01  1.8957323737221003e+01  1.9242912492915349e+00
+   27  8.6190447470516060e-02 -2.3639345383014803e+01  6.2652730906494423e+00
+   28 -1.5812876277619852e+01  6.0673551856385073e+00 -1.0405040442005870e+01
+   29  1.6452389982237243e+01  1.7576623643628043e+01  4.0631933291837985e+00
+...
--- a/unittest/force-styles/tests/mol-pair-morse_smooth_linear.yaml
+++ b/unittest/force-styles/tests/mol-pair-morse_smooth_linear.yaml
@ -0,0 +1,96 @@
+---
+lammps_version: 21 Jul 2020
+date_generated: Tue Aug 11 09:15:04 202
+epsilon: 5e-14
+prerequisites: ! |
+  atom full
+  pair morse/smooth/linear
+pre_commands: ! ""
+post_commands: ! ""
+input_file: in.fourmol
+pair_style: morse/smooth/linear 8.0
+pair_coeff: ! "1 1 0.0202798941614106 2.78203488021395 2.725417159299 \n1 2 0.0101167811264648
+  3.9793050302425 1.90749569018897 \n1 3 0.0202934330695928 2.43948720203264 3.10711749999622
+  \n1 4 0.0175731334238374 2.48316585521317 3.05258880102438 \n1 5 0.0175731334238374
+  2.48316585521317 3.05258880102438 \n2 2 0.00503064360487288 6.98433077606902 1.08960295117864
+  \n2 3 0.0101296013842819 3.31380153807866 2.28919067558352 \n2 4 0.00497405122588691
+  14.0508902925745 0.544416409093563 \n2 5 0.00877114211614446 3.39491256196178 2.23466262511073
+  \n3 3 0.0203039874239943 2.17204344301477 3.48881895084762 \n3 4 0.0175825321440736
+  2.20660439192238 3.43428999287994 \n3 5 0.0175825321440736 2.20660439192238 3.43428999287994
+  \n4 4 0.0152259201379927 2.24227873774009 3.37976131582396 \n4 5 0.0152259201379927
+  2.24227873774009 3.37976131582396 \n5 5 0.0152259201379927 2.24227873774009 3.37976131582396
+  \n"
+extract: ! |
+  d0 2
+  r0 2
+  alpha 2
+natoms: 29
+init_vdwl: 110.576455574558
+init_coul: 0
+init_stress: ! |2-
+   2.0965672593667708e+02  2.1015032692452459e+02  3.3202360755330801e+02 -3.7942655658588343e+01  2.3588817932865467e+01  3.0835767484464419e+01
+init_forces: ! |2
+    1 -3.0480780002327008e+00  2.7921984122028618e+01  3.5405528010927227e+01
+    2  1.7192246011451811e+01  1.4143557582376275e+01 -2.0236514220183114e+01
+    3 -1.4198382794249000e+01 -3.5992270842783007e+01 -1.4439948386213564e+01
+    4 -3.5571543955166662e+00  9.2208514241020678e-01 -2.5349681982497936e+00
+    5 -1.1301072607183411e+00 -1.9175172427659009e+00  5.0830194514203129e+00
+    6 -4.9081806263588575e+01  5.2933354037517596e+01  4.4324760767644200e+01
+    7 -6.5864013709165958e-01 -1.4367994435644658e+01 -9.1085601115349490e+01
+    8  1.1150805850946377e+00 -4.4339866650423687e+00  2.5401312718266635e+01
+    9  7.4783930937568188e+00  8.0676720298458289e+00  3.3115612041353316e+01
+   10  3.3188057609406087e+01 -4.4107423530419425e+01 -1.2533250685202610e+01
+   11 -9.8644754274471402e-01 -2.5309184692840789e+00 -4.1172191247102985e+00
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