specifying categorical features in Python Outlier Detection (PyOD)

Created by: shivasheeshyadav

How to specify the categorical features in PyOD when using Histogram-based Outlier Detection (HBOS) for anomaly detection ? I've read that HBOS can be used for anomaly detection when there are categorical features involved. I found it's Python implementation here: https://pyod.readthedocs.io/en/latest/pyod.models.html#module-pyod.models.hbos But I can't figure out how should I pass the position or list of names of categorical features of my dataset while training the model. The code I've tried:

clf = HBOS(n_bins=10, alpha=0.1, tol=0.5, contamination=0.1)
clf.fit(train_df)
train_pred = clf.labels_

There is no parameter to mention categorical features while training.