dimod.ConstrainedQuadraticModel.add_variable¶

ConstrainedQuadraticModel.add_variable(vartype: Union[dimod.vartypes.Vartype, str, frozenset], v: Optional[Hashable] = None, *, lower_bound: Optional[float] = None, upper_bound: Optional[float] = None) → Hashable[source]¶

Add a variable to the model.

Parameters

vartype –
Variable type. One of:
- SPIN, 'SPIN', {-1, 1}
- BINARY, 'BINARY', {0, 1}
- INTEGER, 'INTEGER'
- REAL, 'REAL'
v – Label for the variable. Defaults to the length of the quadratic model, if that label is available. Otherwise defaults to the lowest available positive integer label.
lower_bound – Lower bound on the variable. Ignored when the variable is BINARY or SPIN.
upper_bound – Upper bound on the variable. Ignored when the variable is BINARY or SPIN.

Returns

Variable label.

Raises

ValueError – If v is already a variable in the model and the vartype, lower_bound, or upper_bound are inconsistent.

Examples

>>> from dimod import ConstrainedQuadraticModel, Integer
>>> cqm = ConstrainedQuadraticModel()
>>> cqm.add_variable('INTEGER', 'i')
'i'