Chapter Contents |
Previous |
Next |

The TRANS Procedure |

**PROC TRANS***options***;**

**CAPACITY=***SAS-data-set*- names the SAS data set that contains the capacity on each arc in the
transportation network. These data specify the maximum allowable flow on
each network arc. If the CAPACITY= option is omitted, then the value of
the DEFCAPACITY= option
is used for each arc in the network.
**COST=***SAS-data-set*- names the SAS data set that contains the cost, supply, and demand data
for the transportation network. If the COST= option is omitted, the most recently
created SAS data set is used.
**MINFLOW=***SAS-data-set*- names the SAS data set that contains the minimum flow data for the
transportation network. These data specify the minimum required flow on
each arc in the network. If the MINFLOW= option is omitted, then the value of
the DEFMINFLOW= option
is used for each arc in the network.

**OUT=***SAS-data-set*- specifies a name for the output data set. If the OUT= option is omitted, the SAS
System creates a data set and names it according to the
DATA
*n*convention. Refer to the section "SAS Statements Used in the Data Set" in base SAS documentation for more information.

**DEFCAPACITY=***c*- specifies the default capacity for the arcs in the network. The default
value of
*c*is . **DEFMINFLOW=***s*- specifies the default minimum flow for the arcs in the network. The
default value of
*s*is 0. **DEMAND=***d*- gives the number of the observation that contains the number of units
demanded at each destination node. The default value of
*d*is 1.0. See the "Demand" section. **MAXIMUM**- tells the procedure to maximize rather than minimize the objective
function.
**NOTHRUNET**- tells PROC TRANS to
drain away any excess supply (the amount that total supply
exceeds total demand) or excess demand (the amount that total demand exceeds
total supply).
If total supply exceeds total demand and if a destination node demands
*d*units of flow, then*at least**d*units and maybe more will flow to that node. Similarly, if total demand exceeds total supply and if a source node supplies*s*units of flow, then*at least**s*units and possibly more will flow from that node. If a transportation problem has unequal total supply and total demand, and you do not specify either the THRUNET or NOTHRUNET option, then PROC TRANS assumes that the problem is infeasible and does not proceed with the optimization. See the "Balancing Total Supply and Total Demand" section for more information. **THRUNET | ADDSUPPLY**- tells the procedure to force through the network any excess
supply (the amount that total supply exceeds total demand) or
any excess
demand (the amount that total demand exceeds total supply), as
is required.
If a transportation problem has unequal total supply and
total demand, and you do not specify either THRUNET or
NOTHRUNET, then
PROC TRANS assumes that the problem is infeasible
and does not proceed with the optimization.
See the "Balancing Total Supply and Total Demand" section for more information.

Chapter Contents |
Previous |
Next |
Top |

Copyright © 1999 by SAS Institute Inc., Cary, NC, USA. All rights reserved.