atan

Arc tangent

Description

float atan(float $num)

Returns the arc tangent of num in radians. atan is the inverse function of tan, which means that $num == tan(atan($num)) for every value of num that is in the domain of atan.

Parameters

num

The argument to process

Return Values

The arc tangent of num in radians.

See Also

  • tan
  • atanh
  • asin
  • acos