Is it possible to force LibreOffice to open a file with a specific program?

[Arn]

I am working on some .dat files, that were created from a lock-in-amplifier (some device to measure signals with a specific frequency). In fact, the files were not created from the lock-in-amp directly, there is a driver software on a computer, that is receiving signals from the amp. Just to be correct.

The files contain tables with data. I have tried to open them with calc, witch first worked fine. I was getting the same dialog, that appears, when opening a .csv file. But now, for some reason LibreOffice wont open these files in calc anymore, even if i use the open dialog in calc. Instead it opens the file in writer.
Is it possible to force LibreOffice to open the file in calc?

I am using Ubuntu 16.04 and LibreOffice 5.1.6.2
(Version: 5.1.6.2 Build ID: 1:5.1.6~rc2-0ubuntu1~xenial3 CPU Threads: 4; OS Version: Linux 4.13; UI Render: default; Locale: en-US (en_US.UTF-8); Calc: group)

• I have reinstalled LibreOffice using the purge command from apt.
• I have also tried renaming the files to .csv, or to remove the file extension.
• I have deleted the folder with the libreoffice folder stored in home/usrName/.config

I know that this question was asked a few times and was always closed. (Why?)

Please Help. Thanks.

[dajare]

Is there any chance you could make a sample (dummy) of one of your *.dat files available?

[Arn]

These files belong to a traineeship at the university i’m studying at. I will ask, if i could post some of them here. This may take a while. Sorry for the long waiting time.

[dajare]

There’s no rush: when you get permission (or if you create a dummy file), just edit your answer to provide information on how to access the sample. And please don’t use the answer area to add new information about your question – just use that edit facility and include the revised information in that question itself. Thanks!