Strange messages on xperm

[Daniel Volinski]

Hi All,

I have downloaded and installed Mathematica 12.2 on two Windows 10 64 bits machines.

Then I proceeded to download and install the latest version of xact form the xact web site.

I proceeded to open a file from the cloud with the first machine and evaluate it.

The evaluation is OK. I closed the file.

In the second machine I try to do the same on the same file in the cloud but I get a message:

xperm.win64 - System Error

The code execution cannot proceed because ML64I3.dll was

not found. Reinstalling may fix this problem.

I reinstalled Mathematica 12.2 and xact in the second machine but the problem persists.

I have used Mathematica 12.1 and xact successfully in both machines until I installed 12.2.

I don't know if this is relevant but here it is:

First Machine:

Edition: Windows 10 Home

Version: 1909

Installed on: 7/14/2019

OS build: 18363.1256

Second Machine:

Edition: Windows 10 Pro Education

Version: 20H2

Installed on: 6/4/2020

OS build: 19042.685

Please advice.

Daniel Volinski

[Thomas Bäckdahl]

Hi!

I recently sent the following message to this mailing list:
"Unfortunately the xPerm executable fails on Mathematica 12.2 under Windows.

If you are upgrading from version 12.1 a temporary fix is to take the file
C:\Program Files\Wolfram Research\Mathematica\12.1\SystemFiles\Links\MathLink\DeveloperKit\Windows-x86-64\SystemAdditions\ml64i3.dll
from the old installation and place somewhere where the new version can find it. One place would be
C:\Users\WhateverYourUsernameIs\AppData\Roaming\Mathematica\Applications\xAct\xPerm\mathlink
"

This is a temporary fix. The problem is that the version of the MathLink protocol changed between the different versions of Mathematica.
The protocol versions themselves are probably forwards and backwards compatible, but they use different dll files.
In Mathematica 12.1 both versions ml64i3.dll and ml64i4.dll are supplied, but in 12.2 only the later.

The latest version of xperm.win64 from 2014-09-24 uses ml64i3.dll. I think Jose therefore should add that dll file to the distribution if Wolfram allows it. An alternative would be to recompile xperm with a never version of MathLink or a different communication protocol, but that might cause problems with older versions of Mathematica.

Regards
Thomas

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[Sukruti]

Hi,

I am facing the same error, xperm.win64 system error, as Daniel Volinski. I tried the temporary fix suggested by Thomas Bäckdahl but it did not work for me.

I am not sure if I installed the xAct package correctly. I just copy-pasted the xAct folder into "C:\Program Files\Wolfram Research\Mathematica\14.0\AddOns\Applications". Not sure if this is a correct way of installing xAct.

If you know of a way to get rid of the xperm.win64 system error, please let me know.

Regards

Sukruti

[Sukruti]

Hi Thomas,

I now realised I didn't correctly try out the temporary fix you suggested. Instead of copy-pasting the file ml64i3.dll to the location  C:\Users\WhateverYourUsernameIs\AppData\Roaming\Mathematica\Applications\xAct\xPerm\mathlink, I mistakenly copy-pasted ml64i4.dll there.

I don't have an earlier version of Mathematica and so don't have the file ml64i3.dll. Can you please upload it on https://www.dllme.com/ so that I can download it and try your solution?

Regards

Sukruti

[Thomas Bäckdahl]

Hi!

The version of xPerm on xact.es does not use the old ml64i3, it uses ml64i4. So if you get some message that the system is missing ml64i3, you have an old version of xAct somewhere on your system that might cause the problem. Look in the Mathematica $Path variable for hints on where to look.

On a windows system I recommend C:\Users\WhateverYourUserNameIs\AppData\Roaming\Mathematica\Applications\xAct

Now, there is also an alternative version xPerm using LibraryLink instead of MathLink.
It can be found here:
https://github.com/wtbgagoa/xpermLibraryLink/tree/main
There is a precompiled dll file for windows, but Alfonso might need to explain how to use this instead of the old MathLink version if the sample file is not enough.

Regards
Thomas

To view this discussion on the web visit https://groups.google.com/d/msgid/xact/c15d0fbf-bbc2-42fa-802b-ab5a31a20d7cn%40googlegroups.com.

[Sukruti]

Hi,

Thanks, Thomas! I did not get an error message mentioning ml64i3 anywhere. Since you mentioned the ml64i3.dll file as a temporary fix for the xperm.win64 system error faced by Daniel Volinski earlier, I assumed this temporary fix could help solve the problem in my case as well. I now understand that this solution is outdated now, especially for a system that does not have an older version of Mathematica.

Maybe using the alternative version of xPerm using LibraryLink, that you shared, could help solve my problem. I'm not completely sure how to go about it though. Will see what I can do...

Regards

Sukruti