{"action":"created","issue":{"url":"https://api.github.com/repos/GalSim-developers/GalSim/issues/713","repository_url":"https://api.github.com/repos/GalSim-developers/GalSim","labels_url":"https://api.github.com/repos/GalSim-developers/GalSim/issues/713/labels{/name}","comments_url":"https://api.github.com/repos/GalSim-developers/GalSim/issues/713/comments","events_url":"https://api.github.com/repos/GalSim-developers/GalSim/issues/713/events","html_url":"https://github.com/GalSim-developers/GalSim/pull/713","id":134758717,"number":713,"title":"#712 Fix error in CCDNoise getVariance function","user":{"login":"rmjarvis","id":623887,"avatar_url":"https://avatars.githubusercontent.com/u/623887?v=3","gravatar_id":"","url":"https://api.github.com/users/rmjarvis","html_url":"https://github.com/rmjarvis","followers_url":"https://api.github.com/users/rmjarvis/followers","following_url":"https://api.github.com/users/rmjarvis/following{/other_user}","gists_url":"https://api.github.com/users/rmjarvis/gists{/gist_id}","starred_url":"https://api.github.com/users/rmjarvis/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/rmjarvis/subscriptions","organizations_url":"https://api.github.com/users/rmjarvis/orgs","repos_url":"https://api.github.com/users/rmjarvis/repos","events_url":"https://api.github.com/users/rmjarvis/events{/privacy}","received_events_url":"https://api.github.com/users/rmjarvis/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":7,"created_at":"2016-02-19T03:05:27Z","updated_at":"2016-02-19T14:06:30Z","closed_at":null,"pull_request":{"url":"https://api.github.com/repos/GalSim-developers/GalSim/pulls/713","html_url":"https://github.com/GalSim-developers/GalSim/pull/713","diff_url":"https://github.com/GalSim-developers/GalSim/pull/713.diff","patch_url":"https://github.com/GalSim-developers/GalSim/pull/713.patch"},"body":"@dkirkby pointed out an error in the CCDNoise getVariance function.  The correct formula is:\r\n```\r\nvar = sky_level/gain + (read_noise/gain)**2\r\n```\r\nThis PR fixes this error.  It also adds some unit tests that check that when CCDNoise adds noise to an image, this is actually the variance of the resulting noise field.\r\n\r\nFor completeness, I also added the same check for Gaussian and Poisson noise, which both passed."},"comment":{"url":"https://api.github.com/repos/GalSim-developers/GalSim/issues/comments/186226884","html_url":"https://github.com/GalSim-developers/GalSim/pull/713#issuecomment-186226884","issue_url":"https://api.github.com/repos/GalSim-developers/GalSim/issues/713","id":186226884,"user":{"login":"rmandelb","id":1454906,"avatar_url":"https://avatars.githubusercontent.com/u/1454906?v=3","gravatar_id":"","url":"https://api.github.com/users/rmandelb","html_url":"https://github.com/rmandelb","followers_url":"https://api.github.com/users/rmandelb/followers","following_url":"https://api.github.com/users/rmandelb/following{/other_user}","gists_url":"https://api.github.com/users/rmandelb/gists{/gist_id}","starred_url":"https://api.github.com/users/rmandelb/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/rmandelb/subscriptions","organizations_url":"https://api.github.com/users/rmandelb/orgs","repos_url":"https://api.github.com/users/rmandelb/repos","events_url":"https://api.github.com/users/rmandelb/events{/privacy}","received_events_url":"https://api.github.com/users/rmandelb/received_events","type":"User","site_admin":false},"created_at":"2016-02-19T14:06:30Z","updated_at":"2016-02-19T14:06:30Z","body":"In case it�s relevant, I have numpy 1.6.1.\n\n"}}