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Problem

Methods for reading, creating and configuring the problem.

Reading from file

readProblem

def readProblem(self, file_name)

Reads the problem from a file.

  • file_name (str) — path to the input file.

Creating programmatically

Expected call order: createProblem → topology and objective setup → initProblem → resource setup → buildProblem.

createProblem

def createProblem(self)

Allocates an empty problem object inside the solver.

setProblemName

def setProblemName(self, name)

Sets a name for the problem.

  • name (str) — problem name.

initProblem

def initProblem(self)

Initializes data structures based on the topology set so far. Must be called before adding resources.

buildProblem

def buildProblem(self)

Finalizes the problem (scales costs, validates structure). Must be called after all topology, objective, and resource data have been set.

Topology

Methods to define the graph structure. Must be called before initProblem.

setNumNodes

def setNumNodes(self, n)

Sets the number of nodes.

  • n (int) — number of nodes.

setOrigin

def setOrigin(self, origin)

Sets the origin node.

  • origin (int) — node id of the origin.

setDestination

def setDestination(self, destination)

Sets the destination node.

  • destination (int) — node id of the destination.

setDirected

def setDirected(self, directed)

Sets whether the graph is directed.

  • directed (bool) — True for a directed graph.

setCyclic

def setCyclic(self, cyclic)

Sets whether the graph is cyclic.

  • cyclic (bool) — True for a cyclic graph.

setSymmetric

def setSymmetric(self, symmetric)

Sets whether arc costs are the same in both directions.

  • symmetric (bool) — True for a symmetric graph.

addArc

def addArc(self, i, j)

Adds a directed arc from node i to node j.

  • i (int) — source node id.
  • j (int) — target node id.

Objective

Methods to set the objective function costs.

setInitCost

def setInitCost(self, value)

Sets the initial (starting) cost of the problem.

  • value (float) — initial cost.

setNodeCost

def setNodeCost(self, id, cost)

Sets the cost of a node.

  • id (int) — node id.
  • cost (float) — cost value.

setNodeCosts

def setNodeCosts(self, costs)

Sets the cost of all nodes at once.

  • costs (list[float]) — one cost per node.

setArcCost

def setArcCost(self, i, j, cost)

Sets the cost of arc (i, j).

  • i (int) — source node id.
  • j (int) — target node id.
  • cost (float) — arc cost.

Resources

Methods to add and configure resources. Must be called after initProblem and before buildProblem.

addResource

def addResource(self, res_type) -> int

Adds a resource of the given type and returns its id.

  • res_type (str) — resource type: "CAP", "TIME", "NODELIM", "TW".

setResBounds

def setResBounds(self, res_id, lb, ub)

Sets the global lower and upper bounds for a resource.

  • res_id (int) — resource id.
  • lb (int) — lower bound.
  • ub (int) — upper bound.

setResNodeBound

def setResNodeBound(self, res_id, node, lb, ub)

Sets the bounds of a resource at a specific node.

  • res_id (int) — resource id.
  • node (int) — node id.
  • lb (int) — lower bound.
  • ub (int) — upper bound.

setResArcConsumption

def setResArcConsumption(self, res_id, i, j, cost)

Sets the consumption of a resource when traversing arc (i, j).

  • res_id (int) — resource id.
  • i (int) — source node id.
  • j (int) — target node id.
  • cost (int) — resource consumption.

setResNodeConsumption

def setResNodeConsumption(self, res_id, i, cost)

Sets the consumption of a resource when visiting node i.

  • res_id (int) — resource id.
  • i (int) — node id.
  • cost (int) — resource consumption.