{"action":"opened","issue":{"url":"https://api.github.com/repos/Theano/Theano/issues/3685","labels_url":"https://api.github.com/repos/Theano/Theano/issues/3685/labels{/name}","comments_url":"https://api.github.com/repos/Theano/Theano/issues/3685/comments","events_url":"https://api.github.com/repos/Theano/Theano/issues/3685/events","html_url":"https://github.com/Theano/Theano/issues/3685","id":118873015,"number":3685,"title":"Complex number cast warning, on compiling conv2d on CPU with FAST_COMPILE","user":{"login":"mjwillson","id":4502,"avatar_url":"https://avatars.githubusercontent.com/u/4502?v=3","gravatar_id":"","url":"https://api.github.com/users/mjwillson","html_url":"https://github.com/mjwillson","followers_url":"https://api.github.com/users/mjwillson/followers","following_url":"https://api.github.com/users/mjwillson/following{/other_user}","gists_url":"https://api.github.com/users/mjwillson/gists{/gist_id}","starred_url":"https://api.github.com/users/mjwillson/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/mjwillson/subscriptions","organizations_url":"https://api.github.com/users/mjwillson/orgs","repos_url":"https://api.github.com/users/mjwillson/repos","events_url":"https://api.github.com/users/mjwillson/events{/privacy}","received_events_url":"https://api.github.com/users/mjwillson/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":0,"created_at":"2015-11-25T16:25:33Z","updated_at":"2015-11-25T16:25:33Z","closed_at":null,"body":"This is despite my not using complex numbers anywhere. Still seems (?) to work despite the warning, but makes me wonder if something wrong is happening internally.\r\n\r\n```\r\nIn [1]: import theano.tensor as T; import theano\r\nIn [2]: input, filters = T.tensor4('input'), T.tensor4('filters')\r\nIn [3]: fn = theano.function([input, filters], T.nnet.conv2d(input, filters), mode='FAST_COMPILE')\r\nIn [4]: fn(np.ones((1,1,1,1), dtype=np.float32), np.ones((1,1,1,1), dtype=np.float32))\r\n/home/matt/venv/theano/lib/python3.4/site-packages/theano/tensor/nnet/conv.py:789: ComplexWarning: Casting complex values to real discards the imaginary part\r\n  1, val, bval, 0)\r\nOut[4]: array([[[[ 1.]]]], dtype=float32)\r\n```\r\n\r\nThe warning doesn't show up when using FAST_RUN."}}