Repository: scikit-learn/scikit-learn
Pull request: [MRG] Add link to ColumnTransformer and user guide to make_column_transformer documentation
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#### Reference Issues/PRs
Fixes #14127
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#### What does this implement/fix? Explain your changes.

1. Added link  to make_column_transformer section in User guide 
2. Added description for transformer and column(s) in parameter description in make_column_transformer

#### Any other comments?


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Problem statement:
add link to ColumnTransformer and user guide to make_column_transformer documentation
Right now the documentation of ``make_column_transformer`` is pretty bare-bones, it doesn't even really describe the arguments.
We should probably link more explicitly to the ColumnTransformer docs. We should also link to the user guide.
Alternatively we could copy and paste the ColumnTransformer docs, but we need a link to the user guide either way.

Hints from issue discussion:
Hi - can I take this issue ? This will be my first contribution . 
 
Thanks 
Sure @getgaurav2 
I would like to take up this issue #WiMLDS 
It's already being worked on @KenitoInc :)
@adrinjalali - can you please confirm if the expectation is to modify the make_column_transformer section in doc/modules/compose.rst  to add link to its user guide and ColumnTransformer  ?
Not in compose.rst. in the class docstring in its .py definition

👍🏻

Commit message: Fixes # 14127  - Made changes after running flake8

Patch to review:
diff --git a/doc/modules/compose.rst b/doc/modules/compose.rst
index 0ac33ce7a4d4a..caa23ecede107 100644
--- a/doc/modules/compose.rst
+++ b/doc/modules/compose.rst
@@ -496,6 +496,8 @@ the transformation::
          [0.5, 0.5],
          [1. , 0. ]])
 
+.. _make_column_transformer:
+
 The :func:`~sklearn.compose.make_column_transformer` function is available
 to more easily create a :class:`~sklearn.compose.ColumnTransformer` object.
 Specifically, the names will be given automatically. The equivalent for the
diff --git a/sklearn/compose/_column_transformer.py b/sklearn/compose/_column_transformer.py
index 7b863ad46649c..410fdb23e9f4c 100644
--- a/sklearn/compose/_column_transformer.py
+++ b/sklearn/compose/_column_transformer.py
@@ -713,9 +713,28 @@ def make_column_transformer(*transformers, **kwargs):
     be given names automatically based on their types. It also does not allow
     weighting with ``transformer_weights``.
 
+    Read more in the :ref:`User Guide <make_column_transformer>`.
+
     Parameters
     ----------
-    *transformers : tuples of transformers and column selections
+    *transformers :  Tuples
+        Tuples of the form ( transformer, column(s))  specifying the
+        transformer objects  to be applied to subsets of the data.
+
+        transformer : estimator or {'passthrough', 'drop'}
+            Estimator must support `fit` and `transform`. Special-cased
+            strings 'drop' and 'passthrough' are accepted as well, to
+            indicate to drop the columns or to pass them through untransformed,
+            respectively.
+        column(s) : string or int, array-like of string or int, slice, \
+boolean mask array or callable
+            Indexes the data on its second axis. Integers are interpreted as
+            positional columns, while strings can reference DataFrame columns
+            by name.  A scalar string or int should be used where
+            ``transformer`` expects X to be a 1d array-like (vector),
+            otherwise a 2d array will be passed to the transformer.
+            A callable is passed the input data `X` and can return any of the
+            above.
 
     remainder : {'drop', 'passthrough'} or estimator, default 'drop'
         By default, only the specified columns in `transformers` are
@@ -768,7 +787,6 @@ def make_column_transformer(*transformers, **kwargs):
                                      ['numerical_column']),
                                     ('onehotencoder', OneHotEncoder(...),
                                      ['categorical_column'])])
-
     """
     # transformer_weights keyword is not passed through because the user
     # would need to know the automatically generated names of the transformers


Code review comments:
diff_hunk: @@ -713,9 +713,28 @@ def make_column_transformer(*transformers, **kwargs):
     be given names automatically based on their types. It also does not allow
     weighting with ``transformer_weights``.
 
+    Read more in the :ref:`User Guide <make_column_transformer>`.
+
     Parameters
     ----------
-    *transformers : tuples of transformers and column selections
+    *transformers :  Tuples
+        Tuples of the form ( transformer, column(s))  specifying the
path: sklearn/compose/_column_transformer.py
text: @user1:
```suggestion
        Tuples of the form (transformer, column(s)) specifying the
```

diff_hunk: @@ -713,9 +713,28 @@ def make_column_transformer(*transformers, **kwargs):
     be given names automatically based on their types. It also does not allow
     weighting with ``transformer_weights``.
 
+    Read more in the :ref:`User Guide <make_column_transformer>`.
+
     Parameters
     ----------
-    *transformers : tuples of transformers and column selections
+    *transformers :  Tuples
path: sklearn/compose/_column_transformer.py
text: @user1:
```suggestion
    *transformers : tuples
```