Issue running this script

Hello, I am new to lammps and am having trouble running this one script. When I run “mpiexec -np 4 lmp_mpi -in in.pour” in the command window, I get this:

“LAMMPS (7 Aug 2019)
OMP_NUM_THREADS environment is not set. Defaulting to 1 thread. (…/comm.cpp:93)
using 1 OpenMP thread(s) per MPI task
ERROR: Unknown command: communicate single vel yes (…/input.cpp:232)
Last command: communicate single vel yes”

Do I need to download some MPI? If so, which is best suited for windows 10? Please let me know. Thanks!

Hello, I am new to lammps and am having trouble running this one script. When I run “mpiexec -np 4 lmp_mpi -in in.pour” in the command window, I get this:

“LAMMPS (7 Aug 2019)
OMP_NUM_THREADS environment is not set. Defaulting to 1 thread. (…/comm.cpp:93)
using 1 OpenMP thread(s) per MPI task
ERROR: Unknown command: communicate single vel yes (…/input.cpp:232)
Last command: communicate single vel yes”

Do I need to download some MPI? If so, which is best suited for windows 10? Please let me know. Thanks!

no. you need to update the syntax of the input file. where did you get it from?
if you look at the in.pour file in the examples/pour/ folder, you will find the correct syntax.

axel.

I believe that command is deprecated and you need to use:

comm_modify

rather than communicate.

https://lammps.sandia.gov/doc/comm_modify.html

-Keith

This is the closest I get I guess.

C:\Users\walee\EK125>mpiexec -np 4 lmp_mpi -in in.pour
LAMMPS (7 Aug 2019)
OMP_NUM_THREADS environment is not set. Defaulting to 1 thread. (…/comm.cpp:93)
using 1 OpenMP thread(s) per MPI task
ERROR: Illegal comm_modify command (…/comm.cpp:341)
Last command: comm_modify single vel yes