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# lex_ge(+Collection1, +Collection2)

Collection1 is lexicographically greater or equal to Collection2

Collection1
  Collection of integers or (domain) variables
Collection2
  Collection of integers or (domain) variables

## Description

Imposes a lexicographic ordering between the two lists. I.e. either is the first element of Collection1 strictly larger than the first element of Collection2, or the first elements are equal and the lexicographic order holds between the two list tails. A non-existing element (i.e. when the end of list is reached) is strictly smaller than any existing element.

This constraint is known as lex_greatereq in the global constraint catalog, but the catalog's definition requires Collection1 and Collection2 to be the same size. It is implemented using Gecode's rel() constraint (variant that takes two IntVarArgs arguments), with the IRT_GQ IntRelType.

## Examples

    [eclipse 40]: lex_ge([5,2,8,9],[5,2,6,2]).

    ...
    Yes (0.00s cpu)
    [eclipse 41]: lex_ge([5,2,3,9], [5,2,3,9]).

    ...
    Yes (0.00s cpu)

    [eclipse 42]: lex_ge([5,2,3,9], [5,2,3]).

    ...
    Yes (0.00s cpu)
    [eclipse 43]: lex_ge([5,2,3,9], [5,3,1]).

    No (0.00s cpu)

## See Also

lex_lt / 2, lex_gt / 2, lex_eq / 2, lex_ne / 2