Lines Matching full:atan
36 //1. The method is based on the relationship of atan2(Y,X) to atan(|Y/X|)
38 // / sign(Y) atan(|Y/X|) if X > 0
40 // \ sign(Y)*pi - sign(Y)*atan(|Y/X|) if X < 0
42 // Thus, atan2(Y,X) is of the form atan2(Y,X) = PI + sgn*atan(|Y/X|)
45 // for atan(|Y/X|).
47 //2. For |Y/X| < 2^(-64), atan(|Y/X|) ~=~ |Y/X|. Hence, atan2(Y,X) is Y/X
49 //3. For |Y/X| >= 2^(65), atan(|Y/X|) ~=~ pi/2. Hence atan2(Y,X) is sign(Y)pi/2.
50 //4. For 2^(-64) <= |Y/X| < 2^(-5), atan(|Y/X|) is approximated by a polynomial
52 //5. For |Y/X| > 2^(5), atan(|Y/X|) = pi/2 + atan(-|X/Y|), and atan(-|X/Y|) is
56 // |Y/X| to approximately 5 significant bits. Hence, atan(|Y/X|) is
58 // atan(|Y/X|) = atan(B) + atan(Z), where Z = (|Y|-B|X|)/(|X|+B|Y|).
