Constr.index

index

This property returns the current index, or order, of the constraint in the underlying constraint matrix.

Return value:

$= -2$ : removed
$= -1$ : not in model
$\geq 0$ : index of the constraint in the model

Note that the index of a constraint may change after subsequent model modifications.

Example usage:

  c = model.getConstrs()[0]
  print(c.index) # Index will be 0