fix(doc): add docstrings for bin_type (#74)

* Update cascade.py

* Update CHANGELOG.rst

CHANGELOG.rst

@@ -30,6 +30,7 @@ Version 0.1.*
 .. |Fix| replace:: :raw-html:`<span class="badge badge-danger">Fix</span>` :raw-latex:`{\small\sc [Fix]}`
 .. |API| replace:: :raw-html:`<span class="badge badge-warning">API Change</span>` :raw-latex:`{\small\sc [API Change]}`
 
+- |Fix| |API| add docstrings for parameter ``bin_type`` (`#74 <https://github.com/LAMDA-NJU/Deep-Forest/pull/74>`__) @xuyxu
 - |Feature| |API| recover the parameter ``min_samples_split`` (`#73 <https://github.com/LAMDA-NJU/Deep-Forest/pull/73>`__) @xuyxu
 - |Fix| fix the breakdown under the corner case where no internal node exists (`#70 <https://github.com/LAMDA-NJU/Deep-Forest/pull/70>`__) @xuyxu
 - |Feature| support python 3.9 (`#69 <https://github.com/LAMDA-NJU/Deep-Forest/pull/69>`__) @xuyxu

deepforest/cascade.py

@@ -213,6 +213,12 @@ def _build_regressor_predictor(
         The number of samples used to construct feature discrete bins. If
         the size of training set is smaller than ``bin_subsample``, then all
         training samples will be used.
+    bin_type : :obj:`{"percentile", "interval"}`, default= :obj:`"percentile"`
+        The type of binner used to bin feature values into integer-valued bins.
+
+        - If ``"percentile"``, each bin will have approximately the same
+          number of distinct feature values.
+        - If ``"interval"``, each bin will have approximately the same size.
     max_layers : :obj:`int`, default=20
         The maximum number of cascade layers in the deep forest. Notice that
         the actual number of layers can be smaller than ``max_layers`` because
@@ -329,6 +335,12 @@ def _build_regressor_predictor(
         The number of samples used to construct feature discrete bins. If
         the size of training set is smaller than ``bin_subsample``, then all
         training samples will be used.
+    bin_type : :obj:`{"percentile", "interval"}`, default= :obj:`"percentile"`
+        The type of binner used to bin feature values into integer-valued bins.
+
+        - If ``"percentile"``, each bin will have approximately the same
+          number of distinct feature values.
+        - If ``"interval"``, each bin will have approximately the same size.
     max_layers : :obj:`int`, default=20
         The maximum number of cascade layers in the deep forest. Notice that
         the actual number of layers can be smaller than ``max_layers`` because