Parsing transmission issue

[P-Mousley]

Current format of io._parse_transmission on line 791 does not account for nexus files which are missing any transmission values. Only has two examples of naming instances for where to find the transmission value

[RBrearton]

These were the only places where I’d seen transmission in nexus files. Has it by any chance moved again?!

Maybe the parser methods should fall back to a brute force search of the nexus file for a name (like transmission or fatt) in the event that the location has moved. What do you think?

[P-Mousley]

the transmission value is missing from the nexus file entirely - hopefully just a shortlived bug. However i think a solution in the short term could be adding in a fall back of setting transmission to 1 if no value is found, along with a warning somewhere that a default value has been set.
A separate full search of the filetree might be useful, but in the longer term we are working with the GDA/DAQ groups to hopefully stabilise the nexus filetree structure

[RBrearton]

I suppose a nice way to do it could be to set the transmission to 1 just before raising the nexus error that triggers the missing metadata warning. That way a warning will still be written to stderr, but the default value won’t be set to None.