ASKSAGE: Sage Q&A Forum - RSS feedhttps://ask.sagemath.org/questions/Q&A Forum for SageenCopyright Sage, 2010. Some rights reserved under creative commons license.Thu, 21 Aug 2014 03:13:28 +0200Simplification of atanhttps://ask.sagemath.org/question/23869/simplification-of-atan/ I'm teaching a course on dynamical systems based on the book by Devaney. Today I tried to show the map $f(\theta)=2\theta$ on the circle using Sage, where $\theta$ is given in radians. I could not find functions already defined to perform addition in $\mathbb{R}$ modulo $2\pi$, so I tried to devise my own. I stumbled upon this problem:
atan(sin(1/5*pi)/cos(1/5*pi))
produces
arctan(4*sin(1/5*pi)/(sqrt(5) + 1)).
Is there a way to obtain `1/5*pi`?
(By the way, _.simplify() does nothing in this case.)
RafaelThu, 21 Aug 2014 03:13:28 +0200https://ask.sagemath.org/question/23869/