Comment #31 on issue 93 by mario.pe...@gmail.com: Square root denesting http://code.google.com/p/sympy/issues/detail?id=93
In https://github.com/sympy/sympy/pull/1131 the example in the inspiring document Denest_en.pdf by jnebos `sqrt(8 - sqrt(2)*sqrt(5 - sqrt(5)) - sqrt(3)*(1 + sqrt(5)))` is denested in two ways: it is solved by _denester (as one can check disabling sqrt_biquadratic_denest) and by sqrt_biquadratic_denest; while _denester can denest only small radicals of sqrt_depth `3`, sqrt_biquadratic_denest can denest fairly large radicals `sqrt(a + b*sqrt(r))`, with `a,b,r` of sqrt_depth `1`, to which the above example belongs; this algorithm works on pretty large expressions, e.g. the following is done in 1.1s on my computer Intel i7 2.80GHz ```
from sympy import * from sympy.simplify.sqrtdenest import sqrt_depth a,b,r=[Add(*[sqrt(i)*(i+j) for i in range(1,j+3)]) for j in range(4,7)] w = a + b*sqrt(r) z = sqrt((w**2).expand()) res = sqrtdenest(z) sqrt_depth(z), len(z.base.args)
(3, 29)
sqrt_depth(res), len(res.args)
(2, 11)
res - w.expand()
0 ``` -- 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.
