The LP Procedure

Missing Values

The LP procedure treats missing values as missing in all rows except those that identify either upper or lower bounds on structural variables. If the row is an upper-bound row, then the type identifier is 'UPPERBD' and the LP procedure treats missing values as $+\infty $. If the row is a lower-bound row, then the type identifier is 'LOWERBD' and the LP procedure treats missing values as 0, except for the variables that are identified as 'UNRSTRT'.