Initializing help system before first use

# problem.addOptnodeCallback

Purpose
Declares an optimal node callback function, called during the branch and bound search, after the LP relaxation has been solved for the current node, and after any internal cuts and heuristics have been applied, but before the Optimizer checks if the current node should be branched. This callback function will be called in addition to any callbacks already added by problem.addOptnodeCallback.
Topic areas
Callback, Branch and Bound Search
Synopsis
`problem.addOptnodeCallback(optnode, data=None, priority=0)`
`infeasible = optnode(cbprob, cbdata)`
Arguments

optnode | The callback function, which takes arguments cbprob, cbdata and infeasible, and has no return value.
data: Any | A user-defined data to be passed to the callback function, optnode.
priority: int | An integer that determines the order in which multiple node-optimal callbacks will be invoked. The callback added with a higher priority will be called before a callback with a lower priority. Set to 0 if not required.
cbprob: problem | The problem passed to the callback function, optnode.
cbdata: Any | The user-defined data passed as data when setting up the callback.

Return value

infeasible: int | The feasibility status. If set to a nonzero value by the user, the current node will be declared infeasible.

Related topics
problem.removeOptnodeCallback, problem.addInfnodeCallback, problem.addIntsolCallback, problem.addNodecutoffCallback, CALLBACKCOUNT_OPTNODE.
Parent Topic Xpress problem object methods

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