DOC: Improved the docstrings of NDFrame

This change includes the following property axes, shape, ndim, size

Author: yeongseon

pandas/core/frame.py

@@ -550,15 +550,39 @@ def _get_axes(N, K, index=index, columns=columns):
     @property
     def axes(self):
         """
-        Return a list with the row axis labels and column axis labels as the
-        only members. They are returned in that order.
+        Return a list representing the axes of the DataFrame.
+
+        It has the row axis labels and column axis labels as the only members.
+        They are returned in that order.
+
+        Examples
+        --------
+        >>> df = pd.DataFrame({'col1': [1, 2], 'col2': [3, 4]})
+        >>> df.axes
+        [RangeIndex(start=0, stop=2, step=1), Index(['coll', 'col2'],
+        dtype='object')]
         """
         return [self.index, self.columns]
 
     @property
     def shape(self):
         """
         Return a tuple representing the dimensionality of the DataFrame.
+
+        See Also
+        --------
+        ndarray.shape
+
+        Examples
+        --------
+        >>> df = pd.DataFrame({'col1': [1, 2], 'col2': [3, 4]})
+        >>> df.shape
+        (2, 2)
+
+        >>> df = pd.DataFrame({'col1': [1, 2], 'col2': [3, 4],
+        ...                    'col3': [5, 6]})
+        >>> df.shape
+        (2, 3)
         """
         return len(self.index), len(self.columns)
 

pandas/core/generic.py

@@ -457,12 +457,49 @@ def axes(self):
 
     @property
     def ndim(self):
-        """Number of axes / array dimensions"""
+        """
+        Return an int representing the number of axes / array dimensions.
+
+        Return 1 if Series. Otherwise return 2 if DataFrame.
+
+        See Also
+        --------
+        ndarray.ndim
+
+        Examples
+        --------
+        >>> s = pd.Series({'a': 1, 'b': 2, 'c': 3})
+        >>> s.ndim
+        1
+
+        >>> df = pd.DataFrame({'col1': [1, 2], 'col2': [3, 4]})
+        >>> df.ndim
+        2
+        """
         return self._data.ndim
 
     @property
     def size(self):
-        """number of elements in the NDFrame"""
+        """
+        Return an int representing the number of elements in this object.
+
+        Return the number of rows if Series. Otherwise return the number of
+        rows times number of columns if DataFrame.
+
+        See Also
+        --------
+        ndarray.size
+
+        Examples
+        --------
+        >>> s = pd.Series({'a': 1, 'b': 2, 'c': 3})
+        >>> s.size
+        3
+
+        >>> df = pd.DataFrame({'col1': [1, 2], 'col2': [3, 4]})
+        >>> df.size
+        4
+        """
         return np.prod(self.shape)
 
     @property