ACOS — Arccosine function¶

ACOS(X)¶

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

Parameters: X – The type shall either be REAL with a magnitude that is less than or equal to one - or the type shall be COMPLEX.
Returns: 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.

Standard:: Fortran 77 and later, for a complex argument Fortran 2008 or later
Class:: Elemental function

Syntax:

RESULT = ACOS(X)

Example:

program test_acos
  real(8) :: x = 0.866_8
  x = acos(x)
end program test_acos

Specific names:

Name	Argument	Return type	Standard
`ACOS(X)`	`REAL(4) X`	`REAL(4)`	Fortran 77 and later
`DACOS(X)`	`REAL(8) X`	`REAL(8)`	Fortran 77 and later

See also:

Inverse function: COS Degrees function: ACOSD