9.6. ACOS

9.6 ACOS — Arccosine function

Description:

ACOS(X) computes the arccosine of X (inverse of COS(X)).

Standard:

Fortran 77 and later, for a complex argument Fortran 2008 or later

Class:

Elemental function

Syntax:

RESULT = ACOS(X)

Arguments:
X The type shall either be REAL with a magnitude that is less than or equal to one - or the type shall be COMPLEX.
Return value:

The return value is of the same type and kind as X. The real part of the result is in radians and lies in the range 0 \leq \Re \acos(x) \leq \pi.

Example: