Exception: no dump file specified

Hello everyone
I am trying to combine neb outputs for further analysis using neb_combine.py, I made sure to use set environment variable “LAMMPS_PYTHON_TOOLS”, and also change my python intepreter with correct version of 2.7.18, Also I following the right command given in the README file ,and specifying the damp1, damp2 …damp8 files at the end of command but still it is showing following error,
can you please suggest me how to approach this problem ?
arslanullah@uffimm13 example_hop1 % python2.7 neb_combine.py -o outfile -b backfile -r dump.neb.1 dump.neb.2 dump.neb.3 dump.neb.4 dump.neb.5 dump.neb.6 dump.neb.7 dump.neb.8

0102030405060708090100110120130140149150151

read 18 snapshots

18 snapshots selected out of 18

assigned columns: id type x y z

Unscaling dump …

Setting …

0102030405060708090100110120130140149150151

read 18 snapshots

18 snapshots selected out of 18

assigned columns: id type x y z

Unscaling dump …

Setting …

0102030405060708090100110120130140149150151

read 18 snapshots

18 snapshots selected out of 18

assigned columns: id type x y z

Unscaling dump …

Setting …

0102030405060708090100110120130140149150151

read 18 snapshots

18 snapshots selected out of 18

assigned columns: id type x y z

Unscaling dump …

Setting …

0102030405060708090100110120130140149150151

read 18 snapshots

18 snapshots selected out of 18

assigned columns: id type x y z

Unscaling dump …

Setting …

0102030405060708090100110120130140149150151

read 18 snapshots

18 snapshots selected out of 18

assigned columns: id type x y z

Unscaling dump …

Setting …

0102030405060708090100110120130140149150151

read 18 snapshots

18 snapshots selected out of 18

assigned columns: id type x y z

Unscaling dump …

Setting …

0102030405060708090100110120130140149150151

read 18 snapshots

18 snapshots selected out of 18

assigned columns: id type x y z

Unscaling dump …

Setting …

Traceback (most recent call last):

File “neb_combine.py”, line 62, in

back = dump(backfile)

File “/usr/local/Cellar/lammps/20220623/share/lammps/tools/python/pizza/dump.py”, line 229, in init

raise Exception(“no dump file specified”)

Exception: no dump file specified

It seems like it’s failing to identify the dump file named “backfile” according to your input. Does that file exist?

Hi Michael_Jacobs
Thanks for indication I solved the problem, the command "neb_combine.py -o outfile -b backfile -r dump1 dump 2… ", can be done as “neb_combine.py -o outfile -r dump1 dump2 …” since -b backfile is an optional command.