Fix undesired UX behavior of DataFrame output in IPython Notebook pandas-dev#10231

Author: danieljl

doc/source/whatsnew/v0.16.2.txt

@@ -25,6 +25,8 @@ New features
 Other enhancements
 ^^^^^^^^^^^^^^^^^^
 
+- Removed duplicate scroll bars in DataFrame HTML representation. In pandas internal, large DataFrame's output will be wrapped with vertical and horizontal scroll bars. It is unnecessary because IPython has "toggle output scrolling" feature. In IPython below v3.0 the output is still wrapped with horizontal scroll bar because the horizontal scroll bar is not included (yet) in "toogle output scrolling" feature. In IPython v3.0 or later it is included so the output's scrollability all handled by IPython. (:issue:`10231`)
+
 .. _whatsnew_0162.api:
 
 Backwards incompatible API changes

pandas/core/format.py

@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 from __future__ import print_function
+from distutils.version import LooseVersion
 # pylint: disable=W0141
 
 import sys
@@ -692,13 +693,20 @@ def _format_col(self, i):
             space=self.col_space
         )
 
-    def to_html(self, classes=None):
+    def to_html(self, classes=None, notebook=False):
         """
         Render a DataFrame to a html table.
+
+        Parameters
+        ----------
+        notebook : {True, False}, optional, default False
+            Whether the generated HTML is for IPython Notebook.
+
         """
         html_renderer = HTMLFormatter(self, classes=classes,
                                       max_rows=self.max_rows,
-                                      max_cols=self.max_cols)
+                                      max_cols=self.max_cols,
+                                      notebook=notebook)
         if hasattr(self.buf, 'write'):
             html_renderer.write_result(self.buf)
         elif isinstance(self.buf, compat.string_types):
@@ -808,7 +816,8 @@ class HTMLFormatter(TableFormatter):
 
     indent_delta = 2
 
-    def __init__(self, formatter, classes=None, max_rows=None, max_cols=None):
+    def __init__(self, formatter, classes=None, max_rows=None, max_cols=None,
+                 notebook=False):
         self.fmt = formatter
         self.classes = classes
 
@@ -823,6 +832,7 @@ def __init__(self, formatter, classes=None, max_rows=None, max_cols=None):
         self.show_dimensions = self.fmt.show_dimensions
         self.is_truncated = (self.max_rows < len(self.fmt.frame) or
                              self.max_cols < len(self.fmt.columns))
+        self.notebook = notebook
 
     def write(self, s, indent=0):
         rs = com.pprint_thing(s)
@@ -890,6 +900,17 @@ def write_result(self, buf):
                                       'not %s') % type(self.classes))
             _classes.extend(self.classes)
 
+        if self.notebook:
+            div_style = ''
+            try:
+                import IPython
+                if IPython.__version__ < LooseVersion('3.0.0'):
+                    div_style = ' style="max-width:1500px;overflow:auto;"'
+            except ImportError:
+                pass
+
+            self.write('<div{0}>'.format(div_style))
+
         self.write('<table border="1" class="%s">' % ' '.join(_classes),
                    indent)
 
@@ -902,6 +923,10 @@ def write_result(self, buf):
             by = chr(215) if compat.PY3 else unichr(215)  # ×
             self.write(u('<p>%d rows %s %d columns</p>') %
                        (len(frame), by, len(frame.columns)))
+
+        if self.notebook:
+            self.write('</div>')
+
         _put_lines(buf, self.elements)
 
     def _write_header(self, indent):

pandas/core/frame.py

@@ -538,10 +538,9 @@ def _repr_html_(self):
             max_cols = get_option("display.max_columns")
             show_dimensions = get_option("display.show_dimensions")
 
-            return ('<div style="max-height:1000px;'
-                    'max-width:1500px;overflow:auto;">\n' +
-                    self.to_html(max_rows=max_rows, max_cols=max_cols,
-                                 show_dimensions=show_dimensions) + '\n</div>')
+            return self.to_html(max_rows=max_rows, max_cols=max_cols,
+                                show_dimensions=show_dimensions,
+                                notebook=True)
         else:
             return None
 
@@ -1349,7 +1348,8 @@ def to_html(self, buf=None, columns=None, col_space=None, colSpace=None,
                 header=True, index=True, na_rep='NaN', formatters=None,
                 float_format=None, sparsify=None, index_names=True,
                 justify=None, bold_rows=True, classes=None, escape=True,
-                max_rows=None, max_cols=None, show_dimensions=False):
+                max_rows=None, max_cols=None, show_dimensions=False,
+                notebook=False):
         """
         Render a DataFrame as an HTML table.
 
@@ -1388,7 +1388,7 @@ def to_html(self, buf=None, columns=None, col_space=None, colSpace=None,
                                            max_rows=max_rows,
                                            max_cols=max_cols,
                                            show_dimensions=show_dimensions)
-        formatter.to_html(classes=classes)
+        formatter.to_html(classes=classes, notebook=notebook)
 
         if buf is None:
             return formatter.buf.getvalue()

pandas/tests/test_format.py

@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 from __future__ import print_function
+from distutils.version import LooseVersion
 import re
 
 from pandas.compat import range, zip, lrange, StringIO, PY3, lzip, u
@@ -14,6 +15,14 @@
 from numpy.random import randn
 import numpy as np
 
+div_style = ''
+try:
+    import IPython
+    if IPython.__version__ < LooseVersion('3.0.0'):
+        div_style = ' style="max-width:1500px;overflow:auto;"'
+except ImportError:
+    pass
+
 from pandas import DataFrame, Series, Index, Timestamp, MultiIndex, date_range, NaT
 
 import pandas.core.format as fmt
@@ -892,7 +901,7 @@ def test_to_html_truncate(self):
         fmt.set_option('display.max_columns',4)
         result = df._repr_html_()
         expected = '''\
-<div style="max-height:1000px;max-width:1500px;overflow:auto;">
+<div{0}>
 <table border="1" class="dataframe">
   <thead>
     <tr style="text-align: right;">
@@ -980,7 +989,7 @@ def test_to_html_truncate(self):
   </tbody>
 </table>
 <p>20 rows × 20 columns</p>
-</div>'''
+</div>'''.format(div_style)
         if sys.version_info[0] < 3:
             expected = expected.decode('utf-8')
         self.assertEqual(result, expected)
@@ -993,7 +1002,7 @@ def test_to_html_truncate_multi_index(self):
         fmt.set_option('display.max_columns',7)
         result = df._repr_html_()
         expected = '''\
-<div style="max-height:1000px;max-width:1500px;overflow:auto;">
+<div{0}>
 <table border="1" class="dataframe">
   <thead>
     <tr>
@@ -1096,7 +1105,7 @@ def test_to_html_truncate_multi_index(self):
   </tbody>
 </table>
 <p>8 rows × 8 columns</p>
-</div>'''
+</div>'''.format(div_style)
         if sys.version_info[0] < 3:
             expected = expected.decode('utf-8')
         self.assertEqual(result, expected)
@@ -1110,7 +1119,7 @@ def test_to_html_truncate_multi_index_sparse_off(self):
         fmt.set_option('display.multi_sparse',False)
         result = df._repr_html_()
         expected = '''\
-<div style="max-height:1000px;max-width:1500px;overflow:auto;">
+<div{0}>
 <table border="1" class="dataframe">
   <thead>
     <tr>
@@ -1206,7 +1215,7 @@ def test_to_html_truncate_multi_index_sparse_off(self):
   </tbody>
 </table>
 <p>8 rows × 8 columns</p>
-</div>'''
+</div>'''.format(div_style)
         if sys.version_info[0] < 3:
             expected = expected.decode('utf-8')
         self.assertEqual(result, expected)