Intel® Fortran Compiler Classic and Intel® Fortran Compiler Developer Guide and Reference
A newer version of this document is available. Customers should click here to go to the newest version.
ACOS
Elemental Intrinsic Function (Generic): Produces the arccosine of x in radians.
result = ACOS (x)
x  |  
      (Input) Must be of type real, where | x | must be less than or equal to 1, or of type complex.  |  
     
Results
The result type and kind are the same as x and is expressed in radians.
If the result is real, the value is expressed in radians and lies in the range 0 <= ACOS(X) <= pi.
If the result is complex, the real part is expressed in radians and lies in the range 0 <= REAL(ACOS (x)) <= pi.
Specific Name  |  
        Argument Type  |  
        Result Type  |  
       
|---|---|---|
ACOS 1  |  
        REAL(4)  |  
        REAL(4)  |  
       
DACOS 1  |  
        REAL(8)  |  
        REAL(8)  |  
       
QACOS 2  |  
        REAL(16)  |  
        REAL(16)  |  
       
1The setting of compiler options specifying real size can affect ACOS and DACOS. 2Or QARCOS.  |  
       ||
Example
ACOS (0.68032123) has the value .8225955.