arccos
| Definition: | atom x2 = arccos(atom x1) |
| Description: | Return an angle with cosine equal to x1. |
| Comments: | The argument, x1, must be in the range -1 to +1 inclusive.
A value between 0 and PI radians will be returned. Multiply by CD_RAD2DEG (defined in pGUI as 180/PI) to convert to degrees. This function may be applied to an atom or sq_arccos() to all elements of a sequence. The rules for sequence operations apply. arccos() is not as fast as arctan(). |
| Example: |
s = arccos(-1) -- s is 3.141592654 |
| Implementation: | See builtins\misc.e (an autoinclude) for details of the actual implementation. |
| See Also: | cos, arcsin, arctan |