The NETFLOW procedure creates and initializes a SAS macro variable called _ORNETFL. After exiting the procedure, you can use %put &_ORNETFL; to view details about the optimization.

When the network simplex method is used, the value of _ORNETFL consists of the following parts:

• ERROR_STATUS, indicating the existence or absence of any errors

• OPT_STATUS, the stage of the optimization, or what solution has been found

Ideally, at the end of a PROC NETFLOW run in which the network simplex method is used, _ORNETFL has the following value:

   ERROR_STATUS=OK OPT_STATUS=OPTIMAL OBJECTIVE=x 
   SOLUTION=OPTIMAL

At the end of a PROC NETFLOW run in which the interior point algorithm is used, _ORNETFL should have the following value:

   ERROR_STATUS=OK SOLUTION=OPTIMAL OBJECTIVE=x
   ITERATIONS=x ITERATING_TIME=x SOLUTION_TIME=x

Nontrailing blank characters that are unnecessary are removed.

If the preprocessor detects that a problem with a network component is infeasible, and you specify that the interior point algorithm should be used, _ORNETFL has the following value:

  ERROR_STATUS=OK SOLUTION=INFEASIBLE 
  ITERATIONS=0 ITERATING_TIME=0 SOLUTION_TIME=0

The same value is assigned to the _ORNETFL macro variable if the preprocessor detects that an LP problem is infeasible.

Table 7.6 lists alternate values for the _ORNETFL value parts.