Bases: object
Represent (mostly) linear programs generated from Datalog.
Returns Arith expression equivalent to expr but of the form A < 0.
:param expr is an Expression Returns an expression equivalent to expr but of the form A < 0.
Given expression, create var = expr and return (var, var=expr).
Remove toplevel embedded and/ors by creating new equalities.
:param exp is an Expression of the form var = (arith11 ^ ... ^ arith1n) | ... | (arithk1 ^ ... ^ arithkn) where arithij is either a variable or an arithmetic expression where the degenerate cases are permitted as well.
:param indicator controls whether the method Returns a single variable (with supporting expressions) or it Returns an expression that has operator with (flat) arguments
Returns a collection of expressions each of one of the following forms: var1 = var2 * ... * varn var1 = var2 + ... + varn var1 = arith
Returns (new-expression, supporting-expressions)
Translate exp into LP constraints without indicator variable.
:param exp is an Expression of the form var = arith :param bounds is a dictionary from variable to its upper bound
Returns [EXP] if it is of the wrong form. Otherwise, translates into the form y = x < 0, and then returns two constraints where upper(x) is the upper bound of the expression x:
-x <= y * upper(x) x < (1 - y) * upper(x)
Taken from section 7.4 of http://www.aimms.com/aimms/download/manuals/ aimms3om_integerprogrammingtricks.pdf
Given the operator, return the corresponding constructor.
Rewrite EXP to a pure LP problem.
:param exp is an Expression of the form var = (arith11 ^ ... ^ arith1n) | ... | (arithk1 ^ ... ^ arithkn) where the degenerate cases are permitted as well.
Returns a collection of expressions each of the form: a1*x1 + ... + an*xn [<=, ==, >=] b.
Rewrite term exp to a pure LP term.
:param exp is an Expression of the form (arith11 ^ ... ^ arith1n) | ... | (arithk1 ^ ... ^ arithkn) where the degenerate cases are permitted as well.
Returns (new-exp, support) where new-exp is a term, and support is a expressions of the following form. a1*x1 + ... + an*xn [<=, ==, >=] b.
Translate and/or operators into times/plus arithmetic.
:param exp is an Expression that takes one of the following forms. var [!]= term1 ^ ... ^ termn var [!]= term1 | ... | termn var [!]= term1 where termi is an indicator variable.
Returns an expression equivalent to exp but without any ands/ors.
Returns number giving an upper bound on the given expr.
:param expr is an Expression :param bounds is a dictionary from tuple versions of variables to the size of their upper bound.
Bases: congress.datalog.arithmetic_solvers.LpLang
Algorithms for translating LpLang into PuLP library problems.
Return PuLP problem for given optimization and constraints.
Returns a pulp.LpProblem.
Return PuLP version of expr.
:param expr is an Expression of one of the following forms. arith arith = arith arith <= arith arith >= arith :param vars is a dictionary from Expression variables to PuLP variables
Returns a PuLP representation of expr.