forked from lijiext/lammps
157 lines
4.2 KiB
Plaintext
157 lines
4.2 KiB
Plaintext
.. index:: jump
|
|
|
|
jump command
|
|
============
|
|
|
|
Syntax
|
|
""""""
|
|
|
|
.. parsed-literal::
|
|
|
|
jump file label
|
|
|
|
* file = filename of new input script to switch to
|
|
* label = optional label within file to jump to
|
|
|
|
Examples
|
|
""""""""
|
|
|
|
.. parsed-literal::
|
|
|
|
jump newfile
|
|
jump in.run2 runloop
|
|
jump SELF runloop
|
|
|
|
Description
|
|
"""""""""""
|
|
|
|
This command closes the current input script file, opens the file with
|
|
the specified name, and begins reading LAMMPS commands from that file.
|
|
Unlike the :doc:`include <include>` command, the original file is not
|
|
returned to, although by using multiple jump commands it is possible
|
|
to chain from file to file or back to the original file.
|
|
|
|
If the word "SELF" is used for the filename, then the current input
|
|
script is re-opened and read again.
|
|
|
|
.. note::
|
|
|
|
The SELF option is not guaranteed to work when the current input
|
|
script is being read through stdin (standard input), e.g.
|
|
|
|
.. parsed-literal::
|
|
|
|
lmp_g++ < in.script
|
|
|
|
since the SELF option invokes the C-library rewind() call, which may
|
|
not be supported for stdin on some systems or by some MPI
|
|
implementations. This can be worked around by using the :ref:`-in command-line argument <start_7>`, e.g.
|
|
|
|
.. parsed-literal::
|
|
|
|
lmp_g++ -in in.script
|
|
|
|
or by using the :ref:`-var command-line argument <start_7>` to pass the script name as a
|
|
variable to the input script. In the latter case, a
|
|
:doc:`variable <variable>` called "fname" could be used in place of
|
|
SELF, e.g.
|
|
|
|
.. parsed-literal::
|
|
|
|
lmp_g++ -var fname in.script < in.script
|
|
|
|
The 2nd argument to the jump command is optional. If specified, it is
|
|
treated as a label and the new file is scanned (without executing
|
|
commands) until the label is found, and commands are executed from
|
|
that point forward. This can be used to loop over a portion of the
|
|
input script, as in this example. These commands perform 10 runs,
|
|
each of 10000 steps, and create 10 dump files named file.1, file.2,
|
|
etc. The :doc:`next <next>` command is used to exit the loop after 10
|
|
iterations. When the "a" variable has been incremented for the tenth
|
|
time, it will cause the next jump command to be skipped.
|
|
|
|
.. parsed-literal::
|
|
|
|
variable a loop 10
|
|
label loop
|
|
dump 1 all atom 100 file.$a
|
|
run 10000
|
|
undump 1
|
|
next a
|
|
jump in.lj loop
|
|
|
|
If the jump *file* argument is a variable, the jump command can be
|
|
used to cause different processor partitions to run different input
|
|
scripts. In this example, LAMMPS is run on 40 processors, with 4
|
|
partitions of 10 procs each. An in.file containing the example
|
|
variable and jump command will cause each partition to run a different
|
|
simulation.
|
|
|
|
.. parsed-literal::
|
|
|
|
mpirun -np 40 lmp_ibm -partition 4x10 -in in.file
|
|
|
|
.. parsed-literal::
|
|
|
|
variable f world script.1 script.2 script.3 script.4
|
|
jump $f
|
|
|
|
Here is an example of a loop which checks every 1000 steps if the
|
|
system temperature has reached a certain value, and if so, breaks out
|
|
of the loop to finish the run. Note that any variable could be
|
|
checked, so long as it is current on the timestep when the run
|
|
completes. As explained on the :doc:`variable <variable>` doc page,
|
|
this can be insured by includig the variable in thermodynamic output.
|
|
|
|
.. parsed-literal::
|
|
|
|
variable myTemp equal temp
|
|
label loop
|
|
variable a loop 1000
|
|
run 1000
|
|
if "${myTemp} < 300.0" then "jump SELF break"
|
|
next a
|
|
jump SELF loop
|
|
label break
|
|
print "ALL DONE"
|
|
|
|
Here is an example of a double loop which uses the if and
|
|
:doc:`jump <jump>` commands to break out of the inner loop when a
|
|
condition is met, then continues iterating thru the outer loop.
|
|
|
|
.. parsed-literal::
|
|
|
|
label loopa
|
|
variable a loop 5
|
|
label loopb
|
|
variable b loop 5
|
|
print "A,B = $a,$b"
|
|
run 10000
|
|
if "$b > 2" then "jump SELF break"
|
|
next b
|
|
jump in.script loopb
|
|
label break
|
|
variable b delete
|
|
next a
|
|
jump SELF loopa
|
|
|
|
Restrictions
|
|
""""""""""""
|
|
|
|
|
|
If you jump to a file and it does not contain the specified label,
|
|
LAMMPS will come to the end of the file and exit.
|
|
|
|
Related commands
|
|
""""""""""""""""
|
|
|
|
:doc:`variable <variable>`, :doc:`include <include>`, :doc:`label <label>`,
|
|
:doc:`next <next>`
|
|
|
|
**Default:** none
|
|
|
|
|
|
.. _lws: http://lammps.sandia.gov
|
|
.. _ld: Manual.html
|
|
.. _lc: Section_commands.html#comm
|