{"action":"created","issue":{"url":"https://api.github.com/repos/astropy/astropy/issues/3362","labels_url":"https://api.github.com/repos/astropy/astropy/issues/3362/labels{/name}","comments_url":"https://api.github.com/repos/astropy/astropy/issues/3362/comments","events_url":"https://api.github.com/repos/astropy/astropy/issues/3362/events","html_url":"https://github.com/astropy/astropy/pull/3362","id":55542898,"number":3362,"title":"Better handling of inputs to Mapping models","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-dev","name":"Affects-dev","color":"eb6420"},{"url":"https://api.github.com/repos/astropy/astropy/labels/Bug","name":"Bug","color":"eb6420"},{"url":"https://api.github.com/repos/astropy/astropy/labels/modeling","name":"modeling","color":"c7def8"}],"state":"open","locked":false,"assignee":null,"milestone":{"url":"https://api.github.com/repos/astropy/astropy/milestones/15","labels_url":"https://api.github.com/repos/astropy/astropy/milestones/15/labels","id":643887,"number":15,"title":"v1.0.0","description":"","creator":{"login":"astrofrog","id":314716,"avatar_url":"https://avatars.githubusercontent.com/u/314716?v=3","gravatar_id":"","url":"https://api.github.com/users/astrofrog","html_url":"https://github.com/astrofrog","followers_url":"https://api.github.com/users/astrofrog/followers","following_url":"https://api.github.com/users/astrofrog/following{/other_user}","gists_url":"https://api.github.com/users/astrofrog/gists{/gist_id}","starred_url":"https://api.github.com/users/astrofrog/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/astrofrog/subscriptions","organizations_url":"https://api.github.com/users/astrofrog/orgs","repos_url":"https://api.github.com/users/astrofrog/repos","events_url":"https://api.github.com/users/astrofrog/events{/privacy}","received_events_url":"https://api.github.com/users/astrofrog/received_events","type":"User","site_admin":false},"open_issues":12,"closed_issues":232,"state":"open","created_at":"2014-04-29T16:03:02Z","updated_at":"2015-01-26T22:01:37Z","due_on":"2015-01-23T05:00:00Z","closed_at":null},"comments":2,"created_at":"2015-01-26T21:51:55Z","updated_at":"2015-01-26T22:02:30Z","closed_at":null,"pull_request":{"url":"https://api.github.com/repos/astropy/astropy/pulls/3362","html_url":"https://github.com/astropy/astropy/pull/3362","diff_url":"https://github.com/astropy/astropy/pull/3362.diff","patch_url":"https://github.com/astropy/astropy/pull/3362.patch"},"body":"This introduces a workaround to the issue raised by @nden in [this comment](https://github.com/astropy/astropy/pull/3297#issuecomment-70105705)\r\n\r\nI'm not super happy about it since it introduces a (very slight, on the order of a few milliseconds) performance regression on evaluated models with a scalar input.  This isn't that critical since it's not something that scales with the size of the input.\r\n\r\nWhat bothers me more is that this fix is for compatibility with an undocumented, sort of unintentional assumption that all `Model.evaluate()` implementations will return one or more array of at least 1 dimension, even for simple arithmetic expressions involving all scalars (this is because the framework already promotes all scalar parameters to 1-D arrays before passing them to `evaluate`).  I think the current assumptions are fairly reasonable, but they're not universal (clearly, as the `Mapping` class broke this assumption), and it's all still a little confusing.  This explanation probably doesn't even make sense to anyone but me, which is cause for concern in of itself."},"comment":{"url":"https://api.github.com/repos/astropy/astropy/issues/comments/71547902","html_url":"https://github.com/astropy/astropy/pull/3362#issuecomment-71547902","issue_url":"https://api.github.com/repos/astropy/astropy/issues/3362","id":71547902,"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":"2015-01-26T22:02:30Z","updated_at":"2015-01-26T22:02:30Z","body":"Rebased and added regression test."}}