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random_element(+Values, -X)

Pick random element from range or collection
Values
Specification of possible values
X
Output variable

Description

Select a random value from the given specification of possible values. The Values specification can be

Min..Max
A range of integers from Min to Max
List
A list of possible values
Array
An array of possible values

Modes and Determinism

Fail Conditions

The range specification is empty or invalid

Examples

    ?- random_element(3 .. 7, X).
    X = 5
    Yes (0.00s cpu)

    ?- random_element([a, b, c, d], X).
    X = a
    Yes (0.00s cpu)

    ?- random_element([](a, b, c, d), X).
    X = c
    Yes (0.00s cpu)

See Also

random / 1, frandom / 1, random_sample / 3, tent_set_random / 2