add ability to remove multiple rfi channels

[kevinawilson]

This changes the expected rfi parameter for plot() from a two-item list to a list of tuples, each one of which represents the low and high frequencies of the band to filter from the plot.

I did not change the version number. The contributor guidelines said that this project uses SemVer for its versioning. In SemVer, any change to the API (like this) requires a new major version number, but you had indicated that backward compatibility was not an issue, so I didn't know if you wanted to make this a minor version increase instead.

I didn't see anything in the README.md that needed to be changed, but obviously it will require an update to the documentation.

[0xCoto]

Thanks a lot for the PR! Would it be possible to update the .rst in the docs as well (particularly the examples and references page) to ensure everything is up-to-date?

As for the versioning, I'd probably consider it a minor release, but a major update is also quite arguable, so feel free to change setup.py based on your gut, and I'd be happy to create a new release (push the update to PyPi).

[kevinawilson]

I can change the .rst files. I'll try to do that this evening.

I have a couple of other things I would like to add, such as the fixed axes for plots. Perhaps you could wait until those are in place to do a major version change.

By the way, do the plots measure simple relative velocity or are they corrected to VLSR? I was discussing my plots on the SARA list serve, and someone noticed that my plots were blue shifted with respect to the expected results. Astropy has a new module that can change the frame of reference from topocentric to VLSR. If you aren't already adjusting for this, perhaps I can add that (with a boolean parameter in plot() to indicate whether to transform the spectrum to the VSLR).

[0xCoto]

I appreciate your interest in contributing to the software Kevin, you've got plenty of good suggestions that I too would like to see being implemented into Virgo. Feel free to take your time and submit a more complete version whenever you wish, with the additions you like.

The plots calculate radial (relative line-of-sight) velocity indeed. Supporting VLSR correction would be awesome to see though. I'm aware you can do such computations with Astropy but never really got to it, although I definitely see the need for this, so if you could also apply this feature as something like plot(vlsr=True/False), that would be perfect! You could also adjust the plot title of the spectra to indicate if VLSR has been corrected (i.e. adjust "Radial Velocity (km/s)") based on the boolean value of the parameter.

[kevinawilson]

I've added the information to the documentation and setup.py. It is ready for review.

[0xCoto]

Is there a typo in the second RFI range at Line 35? Low frequency appears to be higher than the high frequency. Other than that, everything looks good!

[kevinawilson]

The typo has been fixed.