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# cos(+Number, -Result)

Evaluates the trigonometric function cos(Number) and unifies the resulting value with Result.

Number
  A number.
Result
  Output: float or breal.

## Description

This predicate is used by the ECLiPSe compiler to expand evaluable arithmetic expressions. So the call to cos(Number, Result) is equivalent to

        Result is cos(Number)

which should be preferred for portability.

In coroutining mode, if Number is uninstantiated, the call to cos/2 is delayed until this variable is instantiated.

### Modes and Determinism

- cos(+, -) is det

### Exceptions

(4) instantiation fault
  Number is not instantiated (non-coroutining mode only).
(24) number expected
  Number is not of a numeric type.

## Examples

    Success:
        Result is cos(0).			% gives Result = 1.0
        Result is cos(1.2).			% gives Result = 0.362358
        Result is cos(-33).			% gives Result = -0.0132767

## See Also

is / 2