add unit conversion to vashishta pair style

src/MANYBODY/pair_vashishta.cpp

@@ -45,6 +45,7 @@ PairVashishta::PairVashishta(LAMMPS *lmp) : Pair(lmp)
   restartinfo = 0;
   one_coeff = 1;
   manybody_flag = 1;
+  unit_convert_flag = utils::get_supported_conversions(utils::ENERGY);
 
   nelements = 0;
   elements = NULL;
@@ -361,9 +362,15 @@ void PairVashishta::read_file(char *file)
   // open file on proc 0
 
   if (comm->me == 0) {
-    PotentialFileReader reader(lmp, file, "Vashishta");
+    PotentialFileReader reader(lmp, file, "Vashishta", unit_convert_flag);
     char * line;
 
+    // transparently convert units for supported conversions
+
+    int unit_convert = reader.get_unit_convert();
+    double conversion_factor = utils::get_conversion_factor(utils::ENERGY,
+                                                            unit_convert);
+
     while((line = reader.next_line(NPARAMS_PER_LINE))) {
       try {
         ValueTokenizer values(line);
@@ -412,6 +419,14 @@ void PairVashishta::read_file(char *file)
         params[nparams].r0       = values.next_double();
         params[nparams].bigc     = values.next_double();
         params[nparams].costheta = values.next_double();
+
+        if (unit_convert) {
+          params[nparams].bigh *= conversion_factor;
+          params[nparams].bigd *= conversion_factor;
+          params[nparams].bigw *= conversion_factor;
+          params[nparams].bigb *= conversion_factor;
+        }
+
       } catch (TokenizerException & e) {
         error->one(FLERR, e.what());
       }

unittest/formats/test_pair_unit_convert.cpp

@@ -40,7 +40,9 @@ const double ev_convert = utils::get_conversion_factor(utils::ENERGY, utils::MET
 // 1atm in bar
 const double p_convert = 1.01325;
 // relative error for comparing numbers
-const double rel_error = 1.0e-7;
+// cannot use smaller value due to lack of consistency
+// of data in update.cpp. could be 1.0e-12
+const double rel_error = 5.0e-7;
 
 class PairUnitConvertTest : public ::testing::Test {
 protected:
@@ -171,6 +173,49 @@ TEST_F(PairUnitConvertTest, lj_cut)
             EXPECT_NEAR(ev_convert * fold[i][j], f[i][j], fabs(f[i][j] * rel_error));
 }
 
+TEST_F(PairUnitConvertTest, sw)
+{
+    // check if the prerequisite pair style is available
+    if (!info->has_style("pair", "sw")) GTEST_SKIP();
+
+    if (!verbose) ::testing::internal::CaptureStdout();
+    lmp->input->one("units metal");
+    lmp->input->one("read_data test_pair_unit_convert.data");
+    lmp->input->one("pair_style sw");
+    lmp->input->one("pair_coeff * * GaN.sw Ga N");
+    lmp->input->one("run 0 post no");
+    if (!verbose) ::testing::internal::GetCapturedStdout();
+
+    // copy pressure, energy, and force from first step
+    double pold;
+    lmp->output->thermo->evaluate_keyword("press", &pold);
+    double eold = lmp->force->pair->eng_vdwl + lmp->force->pair->eng_coul;
+    double **f  = lmp->atom->f;
+    for (int i = 0; i < 4; ++i)
+        for (int j = 0; j < 3; ++j)
+            fold[i][j] = f[i][j];
+
+    if (!verbose) ::testing::internal::CaptureStdout();
+    lmp->input->one("clear");
+    lmp->input->one("units real");
+    lmp->input->one("read_data test_pair_unit_convert.data");
+    lmp->input->one("pair_style sw");
+    lmp->input->one("pair_coeff * * GaN.sw Ga N");
+    lmp->input->one("run 0 post no");
+    if (!verbose) ::testing::internal::GetCapturedStdout();
+
+    double pnew;
+    lmp->output->thermo->evaluate_keyword("press", &pnew);
+    EXPECT_NEAR(pold, p_convert * pnew, fabs(pnew * rel_error));
+    double enew = lmp->force->pair->eng_vdwl + lmp->force->pair->eng_coul;
+    EXPECT_NEAR(ev_convert * eold, enew, fabs(enew * rel_error));
+
+    f = lmp->atom->f;
+    for (int i = 0; i < 4; ++i)
+        for (int j = 0; j < 3; ++j)
+            EXPECT_NEAR(ev_convert * fold[i][j], f[i][j], fabs(f[i][j] * rel_error));
+}
+
 TEST_F(PairUnitConvertTest, tersoff)
 {
     // check if the prerequisite pair style is available
@@ -256,6 +301,7 @@ TEST_F(PairUnitConvertTest, tersoff_mod)
         for (int j = 0; j < 3; ++j)
             EXPECT_NEAR(ev_convert * fold[i][j], f[i][j], fabs(f[i][j] * rel_error));
 }
+
 TEST_F(PairUnitConvertTest, tersoff_mod_c)
 {
     // check if the prerequisite pair style is available
@@ -342,16 +388,16 @@ TEST_F(PairUnitConvertTest, tersoff_table)
             EXPECT_NEAR(ev_convert * fold[i][j], f[i][j], fabs(f[i][j] * rel_error));
 }
 
-TEST_F(PairUnitConvertTest, sw)
+TEST_F(PairUnitConvertTest, vashishta)
 {
     // check if the prerequisite pair style is available
-    if (!info->has_style("pair", "sw")) GTEST_SKIP();
+    if (!info->has_style("pair", "vashishta")) GTEST_SKIP();
 
     if (!verbose) ::testing::internal::CaptureStdout();
     lmp->input->one("units metal");
     lmp->input->one("read_data test_pair_unit_convert.data");
-    lmp->input->one("pair_style sw");
-    lmp->input->one("pair_coeff * * GaN.sw Ga N");
+    lmp->input->one("pair_style vashishta");
+    lmp->input->one("pair_coeff * * SiC.vashishta Si C");
     lmp->input->one("run 0 post no");
     if (!verbose) ::testing::internal::GetCapturedStdout();
 
@@ -368,8 +414,8 @@ TEST_F(PairUnitConvertTest, sw)
     lmp->input->one("clear");
     lmp->input->one("units real");
     lmp->input->one("read_data test_pair_unit_convert.data");
-    lmp->input->one("pair_style sw");
-    lmp->input->one("pair_coeff * * GaN.sw Ga N");
+    lmp->input->one("pair_style vashishta");
+    lmp->input->one("pair_coeff * * SiC.vashishta Si C");
     lmp->input->one("run 0 post no");
     if (!verbose) ::testing::internal::GetCapturedStdout();