The INTPOINT Procedure

Output Data Sets

For NPSC problems, the procedure determines the flow that should pass through each arc as well as the value that should be assigned to each nonarc variable. The goal is that the minimum flow bounds, capacities, lower and upper value bounds, and side constraints are not violated. This goal is reached when total cost incurred by such a flow pattern and value assignment is feasible and optimal. The solution found must also conserve flow at each node.

For LP problems, the procedure determines the value that should be assigned to each variable. The goal is that the lower and upper value bounds and the constraints are not violated. This goal is reached when the total cost incurred by such a value assignment is feasible and optimal.

The CONOUT= data set can be produced and contains a solution obtained after performing optimization.

CONOUT= Data Set

The variables in the CONOUT= data set depend on whether or not the problem has a network component. If the problem has a network component, the variables and their possible values in an observation are as follows:

_FROM_	a tail node of an arc. This is a missing value if an observation has information about a nonarc variable.
_TO_	a head node of an arc. This is a missing value if an observation has information about a nonarc variable.
_COST_	the cost of an arc or the objective function coefficient of a nonarc variable
_CAPAC_	the capacity of an arc or upper value bound of a nonarc variable
_LO_	the lower flow bound of an arc or lower value bound of a nonarc variable
_NAME_	a name of an arc or nonarc variable
_SUPPLY_	the supply of the tail node of the arc in the observation. This is a missing value if an observation has information about a nonarc variable.
_DEMAND_	the demand of the head node of the arc in the observation. This is a missing value if an observation has information about a nonarc variable.
_FLOW_	the flow through the arc or value of the nonarc variable
_FCOST_	flow cost, the product of _COST_ and _FLOW_
_RCOST_	the reduced cost of the arc or nonarc variable
_ANUMB_	the number of the arc (positive) or nonarc variable (nonpositive); used for warm starting PROC NETFLOW
_TNUMB_	the number of the tail node in the network basis spanning tree; used for warm starting PROC NETFLOW
_STATUS_	the status of the arc or nonarc variable

If the problem does not have a network component, the variables and their possible values in an observation are as follows:

_OBJFN_	the objective function coefficient of a variable
_UPPERBD	the upper value bound of a variable
_LOWERBD	the lower value bound of a variable
_NAME_	the name of a variable
_VALUE_	the value of the variable
_FCOST_	objective function value for that variable; the product of _OBJFN_ and _VALUE_

The variables present in the ARCDATA= data set are present in a CONOUT= data set. For example, if there is a variable called tail in the ARCDATA= data set and you specified the SAS variable list

  
    from tail;
 

then tail is a variable in the CONOUT= data sets instead of _FROM_. Any ID list variables also appear in the CONOUT= data sets.

MPSOUT= Data Set

The MPSOUT= data set contains problem data converted from a PROC INTPOINT format into an MPS-format SAS data set. The six fields, FIELD1 to FIELD6, in the MPSOUT= data set correspond to the six columns in MPS standard. For more information about the MPS-format SAS data set, see Chapter 14, "The MPS-Format SAS Data Set."