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sqrt(+Number, -Result)

-Result is sqrt(+Number)

Evaluates the square root sqrt(Number) and unifies the resulting value with Result.
Number
A number.
Result
Output: float or breal.

Description

Evaluates the square root sqrt(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 sqrt/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 negative.

Examples

Success:
    Result is sqrt(2.0).	% gives Result = 1.4142135623730951
    Result is sqrt(1.0).      	% gives Result = 1.0
    Result is sqrt(49).       	% gives Result = 7.0

Error:
    Result is sqrt(-2).         % arithmetic exception

See Also

is / 2