SpecificationError

exception cultivars.exceptions.SpecificationError

Bases: CultivarsError, ValueError

A model, polynomial, or coefficient set is invalid or inconsistent.

The shapes are fine but the choice is not: an unknown categorical option, an order below its minimum, a sample too short for the requested depth, a result handed to a consumer that does not expose the surface it reads, a transition matrix whose rows do not sum to one. The most common exception in the package, and the one a misspelled keyword lands on. Also a ValueError. The closed lists a message quotes are the Literal aliases in typing, and the check that fires is usually validate_choice, validate_order or validate_transition in _core.

See also

• DimensionError – when the choice is fine and the shape is not.

• typing – the permitted values quoted in the messages.

Example

>>> import numpy as np
>>> from cultivars.univariate.box_jenkins import ARIMA
>>> ARIMA(np.arange(50.0), order=(1, 0, 0), trend="quadratic")
Traceback (most recent call last):
    ...
cultivars.exceptions.SpecificationError: trend must be one of ('n', 'c', 'ct'); got ...
>>> ARIMA(np.arange(50.0), order=(-1, 0, 0))
Traceback (most recent call last):
    ...
cultivars.exceptions.SpecificationError: ...