CCP4 file format is out of date

[tluchko]

The most recent MRC/CCP4 file format is available at https://www.ccpem.ac.uk/mrc_format/mrc2014.php, which is a significant update from the format used in gridDataFormats. CCP-EM maintains a Python library for reading, writing and validating MRC2014 files at https://github.com/ccpem/mrcfile. A simple option is to use this library for reading and writing but this would add an external dependency to gridDataFormats.

I'd be happy to add in support for reading and writing MRC2014 files by using the mrcfile module or update the existing code (which would be read-only support). Is there a preference?

[orbeckst]

Does mrcfile have pip and conda installable packages?

[tluchko]

Yes. It has both pip and Conda packages.

pip install mrcfile

and

conda install --channel conda-forge mrcfile

[orbeckst]

We'd use mrcfile – no need to reinvent the wheel and it's a light-weight dependency.

If you could create a PR then that would be fantastic! Just ping me when you need a review. (And don't forget to add yourself to AUTHORS.)

[tluchko]

OK. I haven't started anything yet, so I don't have a clear idea when this will be ready.

[orbeckst]

Maybe using mrcfile would help with fixing #76 ?

[orbeckst]

@tluchko , PR #100 uses mrcfile. Thank you for the suggestion.

I'd appreciate a code review of PR #100 if you have the time. Thanks.