{"action":"created","issue":{"url":"https://api.github.com/repos/astropy/astropy/issues/3283","labels_url":"https://api.github.com/repos/astropy/astropy/issues/3283/labels{/name}","comments_url":"https://api.github.com/repos/astropy/astropy/issues/3283/comments","events_url":"https://api.github.com/repos/astropy/astropy/issues/3283/events","html_url":"https://github.com/astropy/astropy/pull/3283","id":53922398,"number":3283,"title":"Fix ColDefs.change_ methods","user":{"login":"embray","id":676149,"avatar_url":"https://avatars.githubusercontent.com/u/676149?v=3","gravatar_id":"","url":"https://api.github.com/users/embray","html_url":"https://github.com/embray","followers_url":"https://api.github.com/users/embray/followers","following_url":"https://api.github.com/users/embray/following{/other_user}","gists_url":"https://api.github.com/users/embray/gists{/gist_id}","starred_url":"https://api.github.com/users/embray/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/embray/subscriptions","organizations_url":"https://api.github.com/users/embray/orgs","repos_url":"https://api.github.com/users/embray/repos","events_url":"https://api.github.com/users/embray/events{/privacy}","received_events_url":"https://api.github.com/users/embray/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/astropy/astropy/labels/Affects-release","name":"Affects-release","color":"0052cc"},{"url":"https://api.github.com/repos/astropy/astropy/labels/Bug","name":"Bug","color":"eb6420"},{"url":"https://api.github.com/repos/astropy/astropy/labels/io.fits","name":"io.fits","color":"c7def8"}],"state":"open","locked":false,"assignee":{"login":"embray","id":676149,"avatar_url":"https://avatars.githubusercontent.com/u/676149?v=3","gravatar_id":"","url":"https://api.github.com/users/embray","html_url":"https://github.com/embray","followers_url":"https://api.github.com/users/embray/followers","following_url":"https://api.github.com/users/embray/following{/other_user}","gists_url":"https://api.github.com/users/embray/gists{/gist_id}","starred_url":"https://api.github.com/users/embray/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/embray/subscriptions","organizations_url":"https://api.github.com/users/embray/orgs","repos_url":"https://api.github.com/users/embray/repos","events_url":"https://api.github.com/users/embray/events{/privacy}","received_events_url":"https://api.github.com/users/embray/received_events","type":"User","site_admin":false},"milestone":null,"comments":4,"created_at":"2015-01-09T22:22:37Z","updated_at":"2015-03-11T21:30:02Z","closed_at":null,"pull_request":{"url":"https://api.github.com/repos/astropy/astropy/pulls/3283","html_url":"https://github.com/astropy/astropy/pull/3283","diff_url":"https://github.com/astropy/astropy/pull/3283.diff","patch_url":"https://github.com/astropy/astropy/pull/3283.patch"},"body":"The old PyFITS `ColDefs` class for representing a set of table columns has three methods, [`change_attrib`](http://docs.astropy.org/en/stable/io/fits/api/tables.html#astropy.io.fits.ColDefs.change_attrib), [`change_name`](http://docs.astropy.org/en/stable/io/fits/api/tables.html#astropy.io.fits.ColDefs.change_name), and [`change_unit`](http://docs.astropy.org/en/stable/io/fits/api/tables.html#astropy.io.fits.ColDefs.change_unit) that I fairly frequently get questions about--these should be mentioned in the FAQ.\r\n\r\nThey never really worked properly because although they can change the column objects in-place, they don't actually change the data in the table which is confusing.  They're from a time before PyFITS really had a thought out data model (and it still doesn't really, especially not for tables).  Anyways, using these methods only results in confusion, as do some of the other `ColDefs` methods.  They should all be marked deprecated, and documentation provided for how to perform various tasks for updating FITS tables.  This can serve as a first step to replacing the FITS table interface entirely.\r\n\r\n**UPDATE:** A mentioned in some of the columns below, instead of deprecating these I finally went ahead and tried to fix them instead.  My feeling about this used to be that it was too much trouble to fix within the current interface, and that instead it should wait until the table interface is completely redone to use Astropy Table, and then the whole thing could be scrapped.  But on further thought it wasn't all that hard to fix, and the approach I've taken I think will prove useful in transitioning to Astropy Tables as well."},"comment":{"url":"https://api.github.com/repos/astropy/astropy/issues/comments/78376353","html_url":"https://github.com/astropy/astropy/pull/3283#issuecomment-78376353","issue_url":"https://api.github.com/repos/astropy/astropy/issues/3283","id":78376353,"user":{"login":"embray","id":676149,"avatar_url":"https://avatars.githubusercontent.com/u/676149?v=3","gravatar_id":"","url":"https://api.github.com/users/embray","html_url":"https://github.com/embray","followers_url":"https://api.github.com/users/embray/followers","following_url":"https://api.github.com/users/embray/following{/other_user}","gists_url":"https://api.github.com/users/embray/gists{/gist_id}","starred_url":"https://api.github.com/users/embray/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/embray/subscriptions","organizations_url":"https://api.github.com/users/embray/orgs","repos_url":"https://api.github.com/users/embray/repos","events_url":"https://api.github.com/users/embray/events{/privacy}","received_events_url":"https://api.github.com/users/embray/received_events","type":"User","site_admin":false},"created_at":"2015-03-11T21:30:02Z","updated_at":"2015-03-11T21:30:02Z","body":"It should be noted that this PR does not currently attempt to fix issues with the `ColDefs.add_col` and `ColDefs.del_col` methods.  It adds support for them within the new interface, but they still have more or less the same broken behavior as before.  I will try to address that as a piggy-back to this PR."}}