Normalize (cpmpy.transformations.normalize)

Normalize a toplevel list, or simplify Boolean expressions.

cpmpy.transformations.normalize.simplify_boolean(lst_of_expr: list[Expression], num_context=False) → list[Expression][source]

Removes Boolean constants from CPMpy expressions, except inside global constraints/functions.

Solver interfaces are expected to handle typing of Boolean constants in global constraints/functions themselves. Expects all not operators to have been eliminated by push_down_negation() beforehand (except not over a GlobalConstraint).

Boolean constants are promoted to integers in numerical context (e.g. in wsum); integers are never converted to Booleans.

Parameters:

  • lst_of_expr (list[Expression]) – list of CPMpy expressions

  • num_context (bool) – whether the expressions are used as numeric arguments (default: False)

Returns:

simplified expressions; returns lst_of_expr unchanged if nothing changed

Return type:

list[Expression]

cpmpy.transformations.normalize.toplevel_list(cpm_expr, merge_and=True)[source]

Unravels nested lists and top-level AND’s and ensures every element returned is a CPMpy Expression with is_bool() true.

Parameters:

  • cpm_expr – Expression or list of Expressions

  • merge_and – if True then a toplevel ‘and’ will have its arguments merged at top level