atan2, atan2f : arc tangent of y/x

Synopsis

#include <math.h>
double atan2(double y,double x);
float atan2f(float y,float x);
```### Description

atan2 computes the inverse tangent (arc tangent) of y/x. atan2 produces the correct result even for angles near (that is, when x is near 0). atan2f is identical to atan2, save that it takes and returns float.### Returns

atan2 and atan2f return a value in radians. If both x and y are 0.0, atan2 causes a DOMAIN error. You can modify error handling for these functions using matherr.

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**Authoritative source**: BUSMASTER DITA help source `atan2.dita`, compiled into `BUSMASTER.CHM` with the application.