C atan Function: Purpose & Usage

The atan() function in the C language is used to calculate the arctangent of a given parameter. It returns an angle between -π/2 and π/2 where the tangent value is equal to the input value. Specifically, atan() takes a floating-point number as a parameter and returns its arctangent value in radians.

Here is the prototype of the atan() function:

double atan(double x);

The parameter x is a floating-point number for calculating the arctangent value.

For example, if you call atan(1.0), it will return 45 degrees or π/4 radians because the value of the tangent function at this angle is 1.