Features
- The class `MondrianCategorizer` was added to `crepes.extras`, for generating categories to be used by Mondrian conformal classifiers, regressors and predictive systems. See [the documentation](https://crepes.readthedocs.io/en/latest/crepes.extras.html) for the interface to objects of the class through the `fit` and `apply` methods.
- The class `WrapRegressor` has been updated so that the method `calibrate` allows for specifying an (optional) difficulty estimator and (optional) Mondrian categorizer, which are used both for calibration and making predictions, instead of requiring that difficulty estimates and Mondrian categories are provided separately for these tasks. The methods `predict_int`, `predict_cps` and `evaluate` no longer require `sigmas` and `bins` to be provided for normalized and Mondrian conformal regressors and predictive systems. Thanks to tuvelofstrom for suggestions along these lines.
- The class `WrapClassifier` has been updated so that the method `calibrate` allows for specifying an (optional) Mondrian categorizer, which is used both for calibration and making predictions. The methods `predict_p`, `predict_set` and `evaluate` no longer require `bins` to be provided for Mondrian conformal classifiers.
Fix
- Label vectors represented by pandas.Series are converted to NumPy arrays to avoid indexing issues. Thanks to valeman for pointing this out.