英和和英

出典:『Wikipedia』 (2011/07/19 02:14 UTC 版)

英語による解説

引用

In trigonometry, the two-argument function atan2 is a variation of the arctangent function. For any real arguments x and y not both equal to zero, atan2(y, x) is the angle in radians between the positive x-axis of a plane and the point given by the coordinates (x, y) on it. The angle is positive for counter-clockwise angles (upper half-plane, y > 0), and negative for clockwise angles (lower half-plane, y < 0).