Initializing help system before first use

# problem.getSlacks

Purpose
Obtains the slack values associated with the incumbent solution during or after optimization with problem.optimize, problem.mipOptimize, problem.lpOptimize or problem.nlpOptimize.
Synopsis
`slacks = problem.getSlacks(*constraints)`
Argument

constraints | (optional) constraint objects whose slacks will be returned. If none is provided, a list of slacks for all constraints in the problem will be returned.

Return value

slacks | A list of slack values if *constraints contains more than one constraint object or is not provided, a single slack value otherwise.

Example

    import xpress as xp
    import numpy as np
    p = xp.problem()
    x = p.addVariables(10)
    A = np.random.random((5,10))
    b = np.random.random(5)
    constr = xp.Dot(A,x) >= b
    p.addConstraint(constr)
    p.setObjective(xp.Sum(x))
    p.optimize()
    print("slack of 2nd and 3rd constraint:", p.getSlacks(constr[1], constr[2]))
    print("slack of first three constraints:", p.getSlacks(constr[:3]))

Related topics
problem.optimize, problem.getSolution, problem.getDuals, problem.getRedCosts, problem.getCallbackSlacks, problem.getCallbackPresolveSlacks, constraint.getSlack.
Parent Topic Xpress problem object methods

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