{"action":"created","issue":{"url":"https://api.github.com/repos/astropy/astropy/issues/3889","labels_url":"https://api.github.com/repos/astropy/astropy/issues/3889/labels{/name}","comments_url":"https://api.github.com/repos/astropy/astropy/issues/3889/comments","events_url":"https://api.github.com/repos/astropy/astropy/issues/3889/events","html_url":"https://github.com/astropy/astropy/pull/3889","id":91045516,"number":3889,"title":"Add Sersic1D and Sersic2D model classes. ","user":{"login":"patti","id":4968596,"avatar_url":"https://avatars.githubusercontent.com/u/4968596?v=3","gravatar_id":"","url":"https://api.github.com/users/patti","html_url":"https://github.com/patti","followers_url":"https://api.github.com/users/patti/followers","following_url":"https://api.github.com/users/patti/following{/other_user}","gists_url":"https://api.github.com/users/patti/gists{/gist_id}","starred_url":"https://api.github.com/users/patti/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/patti/subscriptions","organizations_url":"https://api.github.com/users/patti/orgs","repos_url":"https://api.github.com/users/patti/repos","events_url":"https://api.github.com/users/patti/events{/privacy}","received_events_url":"https://api.github.com/users/patti/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/Enhancement","name":"Enhancement","color":"fad8c7"},{"url":"https://api.github.com/repos/astropy/astropy/labels/modeling","name":"modeling","color":"c7def8"}],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":13,"created_at":"2015-06-25T18:48:04Z","updated_at":"2015-06-27T11:07:34Z","closed_at":null,"pull_request":{"url":"https://api.github.com/repos/astropy/astropy/pulls/3889","html_url":"https://github.com/astropy/astropy/pull/3889","diff_url":"https://github.com/astropy/astropy/pull/3889.diff","patch_url":"https://github.com/astropy/astropy/pull/3889.patch"},"body":"I've added model classes for one and two dimensional Sersic surface brightness profiles. Currently there are no derivatives defined for a fit_deriv method. The factor b(n) is calculated with the incomplete gamma function and  solved for numerically. I'm not sure how to go about defining the derivate for this. There are polynomial approximations that could be implemented for different ranges of n. @eteq, thoughts?\r\n@cdeil, @adonath \r\n\r\n[preview docs](https://www.dropbox.com/sh/glr7bwro53ssdva/AADKh-kiM87iVe5Qa6P_z-X7a?dl=0)\r\n\r\n\r\n"},"comment":{"url":"https://api.github.com/repos/astropy/astropy/issues/comments/116009720","html_url":"https://github.com/astropy/astropy/pull/3889#issuecomment-116009720","issue_url":"https://api.github.com/repos/astropy/astropy/issues/3889","id":116009720,"user":{"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},"created_at":"2015-06-27T11:07:34Z","updated_at":"2015-06-27T11:07:34Z","body":"It's running again now: https://ci.appveyor.com/project/Astropy/astropy/build/1.0.1617"}}