MCNPX ver 2.7 error: ''bad problem in xact in routine tpefil chg_mem error''

[alperbugraarslan]

TL;DR

mcnpx ver 2.7 error

I have a problem. Previously mcnpx ver 2.7 was working on my computer. But now I get an error like this. ''bad problem in xact in routine tpefil chg_mem error''. Can anyone help? Am I making a mistake in the installation? Is there something I'm missing when making the ''PATH'' and ''DATAPATH''?.7

 

[Alex A]

Hi @alperbugraarslan, welcome to PhysicsForums.

This is a memory allocation error. If you haven't run out of memory, it might be that something is causing the program to request far too much. This might be a corruption in a library or a mistake in the input file or requesting too many tasks.

I suggest making sure previous run files are out of the way, outp etc, all runt files, either deleted or in another directory and try running a simple input file.

I assume this is in Windows?

 

[alperbugraarslan]

Thank you very much for your answer. I installed the program on my computer with Windows 10 operating system. The program was working without any errors on my previous computer. What do you mean by memory allocation error? I am sure that the previous execution files have been removed (output etc. files). I think there may be an error in the library files or during the creation of ''PATH'' and ''DATAPATH''. I have installed this program on 4 or 5 computers over the years and have never had a problem. This is the first time I have encountered something like this.

 

[Alex A]

The libraries are processed, specified isotopes are read in and any part of the cross section tables that are not needed for the problem are removed. Memory is reallocated for this process. An error in the library, or an out of date or too new library, can break things.

It might be worth doing md5sum on the library directory and see the sums differ from known good copies. Most of the libraries for MCNP/X are now freely available, which might help.

It's possible the data path is wrong, but it is finding the libraries so that seems to be working.

It's possible it could be an xsdir file error, but I wouldn't know how to check this. If you have other versions, you could try those.

You could see if it only affects some problems or some isotope materials. You could try explicitly specifying certain libraries.

I wish I could be more specific, sorry, but good luck!