VBasis

Type: int
Modifiable: Yes

The status of a given variable in the current basis. Possible values are 0 (basic), -1 (non-basic at lower bound), -2 (non-basic at upper bound), and -3 (super-basic). 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.