{"action":"created","issue":{"url":"https://api.github.com/repos/symengine/symengine/issues/672","labels_url":"https://api.github.com/repos/symengine/symengine/issues/672/labels{/name}","comments_url":"https://api.github.com/repos/symengine/symengine/issues/672/comments","events_url":"https://api.github.com/repos/symengine/symengine/issues/672/events","html_url":"https://github.com/symengine/symengine/issues/672","id":120404266,"number":672,"title":"improve sin_table, add cos, tan","user":{"login":"rwst","id":1146709,"avatar_url":"https://avatars.githubusercontent.com/u/1146709?v=3","gravatar_id":"","url":"https://api.github.com/users/rwst","html_url":"https://github.com/rwst","followers_url":"https://api.github.com/users/rwst/followers","following_url":"https://api.github.com/users/rwst/following{/other_user}","gists_url":"https://api.github.com/users/rwst/gists{/gist_id}","starred_url":"https://api.github.com/users/rwst/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/rwst/subscriptions","organizations_url":"https://api.github.com/users/rwst/orgs","repos_url":"https://api.github.com/users/rwst/repos","events_url":"https://api.github.com/users/rwst/events{/privacy}","received_events_url":"https://api.github.com/users/rwst/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":9,"created_at":"2015-12-04T13:43:54Z","updated_at":"2015-12-05T13:53:15Z","closed_at":null,"body":"Recently, I improved these in Pynac to include all values expressible as roots of roots. We could have that in SymEngine too:\r\nhttps://github.com/sagemath/sage/blob/master/src/sage/functions/trig.py#L73\r\n\r\nhttps://github.com/pynac/pynac/blob/master/ginac/inifcns_trans.cpp#L421\r\nhttps://github.com/pynac/pynac/blob/master/ginac/inifcns_trans.cpp#L581\r\nhttps://github.com/pynac/pynac/blob/master/ginac/inifcns_trans.cpp#L735"},"comment":{"url":"https://api.github.com/repos/symengine/symengine/issues/comments/162188876","html_url":"https://github.com/symengine/symengine/issues/672#issuecomment-162188876","issue_url":"https://api.github.com/repos/symengine/symengine/issues/672","id":162188876,"user":{"login":"rwst","id":1146709,"avatar_url":"https://avatars.githubusercontent.com/u/1146709?v=3","gravatar_id":"","url":"https://api.github.com/users/rwst","html_url":"https://github.com/rwst","followers_url":"https://api.github.com/users/rwst/followers","following_url":"https://api.github.com/users/rwst/following{/other_user}","gists_url":"https://api.github.com/users/rwst/gists{/gist_id}","starred_url":"https://api.github.com/users/rwst/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/rwst/subscriptions","organizations_url":"https://api.github.com/users/rwst/orgs","repos_url":"https://api.github.com/users/rwst/repos","events_url":"https://api.github.com/users/rwst/events{/privacy}","received_events_url":"https://api.github.com/users/rwst/received_events","type":"User","site_admin":false},"created_at":"2015-12-05T13:53:14Z","updated_at":"2015-12-05T13:53:14Z","body":"Solving the minimal polynomial with Sympy does not better. So if you really want to automatize this a better solver or simplifier is needed. Try yourself:\r\n```\r\nsage: QQbar(sin(pi/120))               \r\n0.02617694830787315? + 0.?e-19*I\r\nsage: _.minpoly()\r\nx^32 - 8*x^30 + 29*x^28 - 63*x^26 + 23401/256*x^24 - 11963/128*x^22 + 70903/1024*x^20 - 38551/1024*x^18 + 493221/32768*x^16 - 35989/8192*x^14 + 60333/65536*x^12 - 8827/65536*x^10 + 27607/2097152*x^8 - 839/1048576*x^6 + 223/8388608*x^4 - 3/8388608*x^2 + 1/4294967296\r\nsage: sympy.solve(sympy.sympify(_))\r\n[-sqrt(-sqrt(2)*sqrt(-sqrt(-sqrt(5) + sqrt(6)*sqrt(-sqrt(5) + 5) + 7) + 4)/8 + 1/2),\r\n...\r\n```"}}