Hello,
Is there a more stable implementation for the cotangent function than return 1.0/tan(x);?
+10
A:
cot(x) = cos(x)/sin(x) should be more numerically stable close to pi/2 than cot(x) = 1/tan(x). You can implement that efficiently using sincos on platforms that have it.
EDIT: Much better answer: cot(x) = tan(M_PI_2 - x).
Zack
2010-09-17 20:14:24
Ok. I guess this is the best I can do. Also I learnt about sincos, which I must admit I had never met before!
Meh.
2010-09-17 20:35:52
Zack
2010-09-17 21:13:17
+1. Definitely use tan(pi/2 - x).
Alexandre C.
2010-09-17 21:15:37