HEADNODE Statement

The TRANS Procedure

HEADNODE Statement

HEADNODE variables ;

The HEADNODE statement is a list of SAS variables in the COST= data set. Some or all of these variables are in the CAPACITY= data set and the MINFLOW= data set. The names of these SAS variables are also the names of the destination nodes in the transportation problem.

In the COST= data set, the value of a HEADNODE list variable in an observation that does not contain demand data is the cost of transporting a unit of flow from the source node named in that observation's TAILNODE list to the destination node associated with the name of the HEADNODE list variable. HEADNODE variables in the MINFLOW= data set and CAPACITY= data set are similarly associated with destination nodes. In these data sets, the HEADNODE list variables have as values the upper and lower bounds on arc flows.

If the HEADNODE statement is not specified, PROC TRANS forms a HEADNODE list of all numeric variables in the COST= data set not included in the explicit or implicit list specifications.

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