Clarify file extension and formats

[beutlich]

Closes #4704

See also https://github.com/tbeu/Modelica2021_ExternData/blob/02117c93ee96e6d5a5b1115ded46a83fbaa91c5e/modelica2021_ExternData.tex#L132 on the name "Dymola MOS".

[maltelenz]

I object to calling the text file format a Dymola MOS file. Even if Dymola was the first to use it (I assume it was), it has clearly become something tool independent in the decade(s) since then.

[beutlich]

@maltelenz In a constructive manner, please do not state how to not call it but how to call it instead. You can directly edit this PR. Am 2026-01-29 09:06, schrieb Malte Lenz:

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@maltelenz requested changes on this pull request. I object to calling the text file format a Dymola MOS file. Even if Dymola was the first to use it (I assume it was), it has clearly become something tool independent in the decade(s) since then.

[maltelenz]

@beutlich Does it need to be called something except text format like before?

[HansOlsson]

I believe that format precedes my involvement with Dymola, and I'm not even sure if the format is from Dymola or if that text file format for tables is from DLR - possibly as part of ANDECS/DSblock even if we use it in Dymola, can @MartinOtter confirm?

It should not be confused with Dymola's script files (mos-files), as they normally have the extension "txt" not "mos".

I tried to search our documentation and couldn't find any other name than "text file", except possibly "Matlab text file" - even if it isn't from MathWorks - as it's a text-file with the same structure as Matlab v4 file.

[beutlich]

Yes, that is what the issue is about. The term `text format` is ambiguous since CSV is another `text format`. So better to give this special format a proper name. `Dymola MOS` is the best thing I came up so far. Am 2026-01-29 10:56, schrieb Malte Lenz:

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maltelenz left a comment (modelica/ModelicaStandardLibrary#4726) @beutlich Does it need to be called something except `text format` like before?

[HansOlsson]

Based on some internal discussion it seems it was from DLR, and I would propose to call it "DLR matrix text format"

Note that the file extension is usually "txt".
It has nothing to do with Dymola's mos-files.

[beutlich]

Based on some internal discussion it seems it was from DLR, and I would propose to call it "DLR matrix text format"

Note that the file extension is usually "txt". It has nothing to do with Dymola's mos-files.

Thanks. We have a name finally. The PR is revised accordingly. Note, that any file extension is technically legal for the "DLR matrix text format". Only CSV format needs to have .csv extension and MAT-File format needs to have .mat extension. This is also made explicit by this PR.

Dismissing blocking review as my concern was resolved, and I have no further opinions on the PR.