Expression Simplification using SymPy trigsymp

Question

Why does the following simple example not return 1?

from sympy import *

r, theta, phi = symbols('r, theta, phi')
pprint(trigsimp(cos(phi)**2 * sin(theta)**2+sin(phi)**2 * sin(theta)**2  
+ cos(theta)**2))

Instead, I get

   2       2         2       2         2         2   
sin (φ)⋅sin (θ) - cos (φ)⋅cos (θ) + cos (φ) + cos (θ)

the same for simplify().

FWIW, I get 1 from your code in sympy 0.7.6.1. – DSM Dec 06 '15 at 15:47 — DSM, Dec 06 '15 at 15:47
I have 0.7.1, so this really might be the simple problem – pawel_winzig Dec 06 '15 at 16:15 — pawel_winzig, Dec 06 '15 at 16:15

score 1 · Answer 1 · answered Dec 07 '15 at 09:14

1

It seems to be only a version issue, in sympy 0.7.6.1 it works fine

answered Dec 07 '15 at 09:14

pawel_winzig

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Expression Simplification using SymPy trigsymp

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