{"action":"created","issue":{"url":"https://api.github.com/repos/cbm755/octsympy/issues/274","labels_url":"https://api.github.com/repos/cbm755/octsympy/issues/274/labels{/name}","comments_url":"https://api.github.com/repos/cbm755/octsympy/issues/274/comments","events_url":"https://api.github.com/repos/cbm755/octsympy/issues/274/events","html_url":"https://github.com/cbm755/octsympy/issues/274","id":122416028,"number":274,"title":"inv matrix det 0","user":{"login":"latot","id":10523095,"avatar_url":"https://avatars.githubusercontent.com/u/10523095?v=3","gravatar_id":"","url":"https://api.github.com/users/latot","html_url":"https://github.com/latot","followers_url":"https://api.github.com/users/latot/followers","following_url":"https://api.github.com/users/latot/following{/other_user}","gists_url":"https://api.github.com/users/latot/gists{/gist_id}","starred_url":"https://api.github.com/users/latot/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/latot/subscriptions","organizations_url":"https://api.github.com/users/latot/orgs","repos_url":"https://api.github.com/users/latot/repos","events_url":"https://api.github.com/users/latot/events{/privacy}","received_events_url":"https://api.github.com/users/latot/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/cbm755/octsympy/labels/enhancement","name":"enhancement","color":"84b6eb"}],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":9,"created_at":"2015-12-16T02:55:01Z","updated_at":"2016-01-10T07:18:51Z","closed_at":null,"body":"Hi :D \r\n\r\nWell here a little problem, its when matrix have det 0, in a simple ex:\r\n\r\n```\r\n>> syms a\r\nOctSymPy v2.2.4: this is free software without warranty, see source.\r\nInitializing communication with SymPy using a popen2() pipe.\r\nSome output from the Python subprocess (pid 1594) might appear next.\r\nPython 2.7.10 (default, Nov 19 2015, 11:51:46) \r\n[GCC 4.9.3] on linux2\r\nType \"help\", \"copyright\", \"credits\" or \"license\" for more information.\r\n>>> >>> \r\nOctSymPy: Communication established.  SymPy v0.7.6.\r\n>> det([a,a;a,a])\r\nans = (sym) 0\r\n>> inv([a,a;a,a])\r\nTraceback (most recent call last):\r\n  File \"<stdin>\", line 10, in <module>\r\n  File \"<stdin>\", line 6, in _fcn\r\n  File \"/usr/lib64/python2.7/site-packages/sympy/matrices/matrices.py\", line 309, in inv\r\n    return self._eval_inverse(**kwargs)\r\n  File \"/usr/lib64/python2.7/site-packages/sympy/matrices/dense.py\", line 306, in _eval_inverse\r\n    rv = M.inverse_GE(iszerofunc=iszerofunc)\r\n  File \"/usr/lib64/python2.7/site-packages/sympy/matrices/matrices.py\", line 2631, in inverse_GE\r\n    raise ValueError(\"Matrix det == 0; not invertible.\")\r\nValueError: Matrix det == 0; not invertible.\r\n\r\nPYTHON: Error in cmd\r\nResetting the octsympy communication mechanism\r\nClosing the Python pipe...\r\nerror: python_cmd: unexpected return\r\nerror: called from\r\n    python_cmd at line 144 column 6\r\n    inv at line 41 column 5\r\n```\r\n\r\nWell obs this can happend with more complex expresions.\r\n\r\nCya."},"comment":{"url":"https://api.github.com/repos/cbm755/octsympy/issues/comments/170322846","html_url":"https://github.com/cbm755/octsympy/issues/274#issuecomment-170322846","issue_url":"https://api.github.com/repos/cbm755/octsympy/issues/274","id":170322846,"user":{"login":"cbm755","id":818622,"avatar_url":"https://avatars.githubusercontent.com/u/818622?v=3","gravatar_id":"","url":"https://api.github.com/users/cbm755","html_url":"https://github.com/cbm755","followers_url":"https://api.github.com/users/cbm755/followers","following_url":"https://api.github.com/users/cbm755/following{/other_user}","gists_url":"https://api.github.com/users/cbm755/gists{/gist_id}","starred_url":"https://api.github.com/users/cbm755/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/cbm755/subscriptions","organizations_url":"https://api.github.com/users/cbm755/orgs","repos_url":"https://api.github.com/users/cbm755/repos","events_url":"https://api.github.com/users/cbm755/events{/privacy}","received_events_url":"https://api.github.com/users/cbm755/received_events","type":"User","site_admin":false},"created_at":"2016-01-10T07:18:51Z","updated_at":"2016-01-10T07:18:51Z","body":"Sorry, I don't understand your comment.  `zoo` is complex infinity.  The issue for scalar `x` is whether a user would expect `inv(x)` to do the same as `1/x`.\r\n\r\n(Note for matrices, it might be different: Octave users will generally expect `inv` to mean \"compute the inverse\" whereas slash means \"solve a linear system\" (e.g., with Gaussian Elimination).)\r\n\r\nFile a PR if you have a specific change you want here."}}