Status: Accepted Owner: smichr Labels: Type-Defect Priority-High New issue 1538 by smichr: root of negative number http://code.google.com/p/sympy/issues/detail?id=1538
Can someone find out where this is originiting? Sympy can correctly compute 1/imag_number and can compute the nth rooth of a negative number but is having problems with 1/nth_root_of_negative: >>> a=(-65)**(S(1)/6) >>> a.evalf() 1.73205080756888 + I #so there's an imaginary number if you take that evaluated value and invert it, all is ok >>> print (1/a.evalf()).evalf() 0.431895228023866 - 0.249354826161294*I #this is the correct value but if you evaluate after taking the ratio, it's wrong >>> (1/a).evalf() 0.431895228023866 + 0.249354826161294*I #this is wrong If there is an exact nth root exptractable then the right answer is obtained. Note in the following that both results are the same: >>> a=(-64)**(S(1)/6);print (1/a.evalf()).evalf(),(1/a).evalf() 0.433012701892219 - 0.25*I 0.433012701892219 - 0.25*I /c -- You received this message because you are listed in the owner or CC fields of this issue, or because you starred this issue. You may adjust your issue notification preferences at: http://code.google.com/hosting/settings --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sympy-issues" group. To post to this group, send email to sympy-issues@googlegroups.com To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en -~----------~----~----~----~------~----~------~--~---
