{"action":"closed","number":10135,"pull_request":{"url":"https://api.github.com/repos/sympy/sympy/pulls/10135","id":50471527,"html_url":"https://github.com/sympy/sympy/pull/10135","diff_url":"https://github.com/sympy/sympy/pull/10135.diff","patch_url":"https://github.com/sympy/sympy/pull/10135.patch","issue_url":"https://api.github.com/repos/sympy/sympy/issues/10135","number":10135,"state":"closed","locked":false,"title":"Fix incorrect assignment of free variables in 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variables to each other:\r\n\r\n```python\r\na, b, c, d, e = symbols('a, b, c, d, e')\r\nAugmatrix = Matrix([[0, 1, 0, 0, 0, 0], [0, 0, 0, 1, 0, 0]])\r\nlinsolve(Augmatrix, a, b, c, d, e)\r\n```\r\n\r\nwould give `{(c, 0, a, 0, e)}` whereas the correct answer is of course `{(a, 0, c, 0, e)}`.\r\n\r\nThe first commit solves this problem by setting the `free_var_index` to be the correctly permuted free variable indices in `gauss_jordan_solve`, and the second adds in the test above.\r\n\r\n\r\n\r\n","created_at":"2015-11-12T04:45:40Z","updated_at":"2015-11-19T11:36:00Z","closed_at":"2015-11-19T11:36:00Z","merged_at":"2015-11-19T11:36:00Z","merge_commit_sha":"3c8b16447d8cf6cdbffd9f7e176a3db0ab3d72ec","assignee":null,"milestone":null,"commits_url":"https://api.github.com/repos/sympy/sympy/pulls/10135/commits","review_comments_url":"https://api.github.com/repos/sympy/sympy/pulls/10135/comments","review_comment_url":"https://api.github.com/repos/sympy/sympy/pulls/comments{/number}","comments_url":"https://api.github.com/repos/sympy/sympy/issues/10135/comments","statuses_url":"https://api.github.com/repos/sympy/sympy/statuses/53cff31bd858e60748c8bfec4813e1cf2f44dd73","head":{"label":"MooVI:linsolve-pr","ref":"linsolve-pr","sha":"53cff31bd858e60748c8bfec4813e1cf2f44dd73","user":{"login":"MooVI","id":1942866,"avatar_url":"https://avatars.githubusercontent.com/u/1942866?v=3","gravatar_id":"","url":"https://api.github.com/users/MooVI","html_url":"https://github.com/MooVI","followers_url":"https://api.github.com/users/MooVI/followers","following_url":"https://api.github.com/users/MooVI/following{/other_user}","gists_url":"https://api.github.com/users/MooVI/gists{/gist_id}","starred_url":"https://api.github.com/users/MooVI/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/MooVI/subscriptions","organizations_url":"https://api.github.com/users/MooVI/orgs","repos_url":"https://api.github.com/users/MooVI/repos","events_url":"https://api.github.com/users/MooVI/events{/privacy}","received_events_url":"https://api.github.com/users/MooVI/received_events","type":"User","site_admin":false},"repo":{"id":46010270,"name":"sympy","full_name":"MooVI/sympy","owner":{"login":"MooVI","id":1942866,"avatar_url":"https://avatars.githubusercontent.com/u/1942866?v=3","gravatar_id":"","url":"https://api.github.com/users/MooVI","html_url":"https://github.com/MooVI","followers_url":"https://api.github.com/users/MooVI/followers","following_url":"https://api.github.com/users/MooVI/following{/other_user}","gists_url":"https://api.github.com/users/MooVI/gists{/gist_id}","starred_url":"https://api.github.com/users/MooVI/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/MooVI/subscriptions","organizations_url":"https://api.github.com/users/MooVI/orgs","repos_url":"https://api.github.com/users/MooVI/repos","events_url":"https://api.github.com/users/MooVI/events{/privacy}","received_events_url":"https://api.github.com/users/MooVI/received_events","type":"User","site_admin":false},"private":false,"html_url":"https://github.com/MooVI/sympy","description":"A 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