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acos(+Number, -Result)
-Result is acos(+Number)
Evaluates the trigonometric function acos(Number) and unifies the resulting
value with Result.
- Number
- A number.
- Result
- Output: float.
Description
Evaluates the trigonometric function acos(Number) and unifies the resulting
value with Result.
This predicate can be used as a function in arithmetic expressions.
In coroutining mode, if Number is uninstantiated, the call to acos/2 is
delayed until this variable is instantiated.
Modes and Determinism
Exceptions
- (4) instantiation fault
- Number is not instantiated (non-coroutining mode only).
- (24) number expected
- Number is not of a numeric type.
- (20) arithmetic exception
- Illegal arithmetic operation: Number is greater than 1 or less than -1.
- (141) unimplemented functionality
- Argument is of type breal
Examples
Success:
Result is acos(1.0). % gives Result = 0.0).
Result is acos(-0.5). % gives Result = 2.0944
Result is acos(0). % gives Result = 1.5708
Error:
Result is acos(2.0). % arithmetic exception
See Also
is / 2