Type: int
Modifiable: Yes

The status of a given linear constraint in the current basis. Possible values are 0 (basic) or -1 (non-basic). A constraint is basic when its slack variable is in the simplex basis. Note that, if you wish to specify an advanced starting basis, you must set basis status information for all constraints and variables in the model. Only available for basic solutions.

Note that if you provide a valid starting extreme point, either through PStart, DStart, or through VBasis, CBasis, then LP presolve will be disabled by default. For models where presolve greatly reduces the problem size, this might hurt performance. For presolve to be enabled, the parameter LPWarmStart must be set to 2.

For examples of how to query or modify attributes, refer to our Attribute Examples.