The ACOS function returns the angle, expressed in radians, whose cosine is X (i.e., the arc-cosine). The range of ACOS is between 0 and p .

Calling Sequence

Result = ACOS( X )



The cosine of the desired angle in the range (-1 <= X <= 1). If X is double-precision floating, the result of ACOS is also double-precision. X cannot be complex. All other types are converted to single-precision floating-point and yield floating-point results. If X is an array, the result has the same structure, with each element containing the arc-cosine of the corresponding element of X .


To find the arc-cosine of 0.707 and store the result in the variable B, enter:

B = ACOS(0.707)

See Also