ENH: Add to_latex() method to Series (#16180) (#16465)

* ENH: Add to_latex() method to Series (#16180)

This changeset adds _repr_latex_ to the Series class and moves
the to_latex() method from the DataFrame class to the NDFrame
class.

* Add Series to_latex test

* Move _repr_latex_ to NDFrame

Streamline things a bit by moving _repr_latex_ methods out of
the Series and DataFrame classes

* DOC: Added versionchanged

(cherry picked from commit 6a6227d)

Author: bsweger

doc/source/api.rst

@@ -724,6 +724,7 @@ Serialization / IO / Conversion
    Series.to_dense
    Series.to_string
    Series.to_clipboard
+   Series.to_latex
 
 Sparse
 ~~~~~~

doc/source/whatsnew/v0.20.2.txt

@@ -20,6 +20,7 @@ Enhancements
 ~~~~~~~~~~~~
 
 - Unblocked access to additional compression types supported in pytables: 'blosc:blosclz, 'blosc:lz4', 'blosc:lz4hc', 'blosc:snappy', 'blosc:zlib', 'blosc:zstd' (:issue:`14478`)
+- ``Series`` provides a ``to_latex`` method (:issue:`16180`)
 
 .. _whatsnew_0202.performance:
 

pandas/core/frame.py

@@ -620,16 +620,6 @@ def _repr_html_(self):
         else:
             return None
 
-    def _repr_latex_(self):
-        """
-        Returns a LaTeX representation for a particular Dataframe.
-        Mainly for use with nbconvert (jupyter notebook conversion to pdf).
-        """
-        if get_option('display.latex.repr'):
-            return self.to_latex()
-        else:
-            return None
-
     @property
     def style(self):
         """
@@ -1596,94 +1586,6 @@ def to_html(self, buf=None, columns=None, col_space=None, header=True,
         if buf is None:
             return formatter.buf.getvalue()
 
-    @Substitution(header='Write out column names. If a list of string is given, \
-it is assumed to be aliases for the column names.')
-    @Appender(fmt.common_docstring + fmt.return_docstring, indents=1)
-    def to_latex(self, buf=None, columns=None, col_space=None, header=True,
-                 index=True, na_rep='NaN', formatters=None, float_format=None,
-                 sparsify=None, index_names=True, bold_rows=True,
-                 column_format=None, longtable=None, escape=None,
-                 encoding=None, decimal='.', multicolumn=None,
-                 multicolumn_format=None, multirow=None):
-        r"""
-        Render a DataFrame to a tabular environment table. You can splice
-        this into a LaTeX document. Requires \usepackage{booktabs}.
-
-        `to_latex`-specific options:
-
-        bold_rows : boolean, default True
-            Make the row labels bold in the output
-        column_format : str, default None
-            The columns format as specified in `LaTeX table format
-            <https://en.wikibooks.org/wiki/LaTeX/Tables>`__ e.g 'rcl' for 3
-            columns
-        longtable : boolean, default will be read from the pandas config module
-            Default: False.
-            Use a longtable environment instead of tabular. Requires adding
-            a \usepackage{longtable} to your LaTeX preamble.
-        escape : boolean, default will be read from the pandas config module
-            Default: True.
-            When set to False prevents from escaping latex special
-            characters in column names.
-        encoding : str, default None
-            A string representing the encoding to use in the output file,
-            defaults to 'ascii' on Python 2 and 'utf-8' on Python 3.
-        decimal : string, default '.'
-            Character recognized as decimal separator, e.g. ',' in Europe.
-
-            .. versionadded:: 0.18.0
-
-        multicolumn : boolean, default True
-            Use \multicolumn to enhance MultiIndex columns.
-            The default will be read from the config module.
-
-            .. versionadded:: 0.20.0
-
-        multicolumn_format : str, default 'l'
-            The alignment for multicolumns, similar to `column_format`
-            The default will be read from the config module.
-
-            .. versionadded:: 0.20.0
-
-        multirow : boolean, default False
-            Use \multirow to enhance MultiIndex rows.
-            Requires adding a \usepackage{multirow} to your LaTeX preamble.
-            Will print centered labels (instead of top-aligned)
-            across the contained rows, separating groups via clines.
-            The default will be read from the pandas config module.
-
-            .. versionadded:: 0.20.0
-
-        """
-        # Get defaults from the pandas config
-        if longtable is None:
-            longtable = get_option("display.latex.longtable")
-        if escape is None:
-            escape = get_option("display.latex.escape")
-        if multicolumn is None:
-            multicolumn = get_option("display.latex.multicolumn")
-        if multicolumn_format is None:
-            multicolumn_format = get_option("display.latex.multicolumn_format")
-        if multirow is None:
-            multirow = get_option("display.latex.multirow")
-
-        formatter = fmt.DataFrameFormatter(self, buf=buf, columns=columns,
-                                           col_space=col_space, na_rep=na_rep,
-                                           header=header, index=index,
-                                           formatters=formatters,
-                                           float_format=float_format,
-                                           bold_rows=bold_rows,
-                                           sparsify=sparsify,
-                                           index_names=index_names,
-                                           escape=escape, decimal=decimal)
-        formatter.to_latex(column_format=column_format, longtable=longtable,
-                           encoding=encoding, multicolumn=multicolumn,
-                           multicolumn_format=multicolumn_format,
-                           multirow=multirow)
-
-        if buf is None:
-            return formatter.buf.getvalue()
-
     def info(self, verbose=None, buf=None, max_cols=None, memory_usage=None,
              null_counts=None):
         """

pandas/core/generic.py

@@ -46,7 +46,7 @@
 import pandas.core.common as com
 import pandas.core.missing as missing
 from pandas.io.formats.printing import pprint_thing
-from pandas.io.formats.format import format_percentiles
+from pandas.io.formats.format import format_percentiles, DataFrameFormatter
 from pandas.tseries.frequencies import to_offset
 from pandas import compat
 from pandas.compat.numpy import function as nv
@@ -1051,6 +1051,16 @@ def __setstate__(self, state):
     # ----------------------------------------------------------------------
     # IO
 
+    def _repr_latex_(self):
+        """
+        Returns a LaTeX representation for a particular object.
+        Mainly for use with nbconvert (jupyter notebook conversion to pdf).
+        """
+        if config.get_option('display.latex.repr'):
+            return self.to_latex()
+        else:
+            return None
+
     # ----------------------------------------------------------------------
     # I/O Methods
 
@@ -1489,6 +1499,100 @@ def to_xarray(self):
                                 coords=coords,
                                 )
 
+    _shared_docs['to_latex'] = """
+        Render an object to a tabular environment table. You can splice
+        this into a LaTeX document. Requires \\usepackage{booktabs}.
+
+        .. versionchanged:: 0.20.2
+           Added to Series
+
+        `to_latex`-specific options:
+
+        bold_rows : boolean, default True
+            Make the row labels bold in the output
+        column_format : str, default None
+            The columns format as specified in `LaTeX table format
+            <https://en.wikibooks.org/wiki/LaTeX/Tables>`__ e.g 'rcl' for 3
+            columns
+        longtable : boolean, default will be read from the pandas config module
+            Default: False.
+            Use a longtable environment instead of tabular. Requires adding
+            a \\usepackage{longtable} to your LaTeX preamble.
+        escape : boolean, default will be read from the pandas config module
+            Default: True.
+            When set to False prevents from escaping latex special
+            characters in column names.
+        encoding : str, default None
+            A string representing the encoding to use in the output file,
+            defaults to 'ascii' on Python 2 and 'utf-8' on Python 3.
+        decimal : string, default '.'
+            Character recognized as decimal separator, e.g. ',' in Europe.
+
+            .. versionadded:: 0.18.0
+
+        multicolumn : boolean, default True
+            Use \multicolumn to enhance MultiIndex columns.
+            The default will be read from the config module.
+
+            .. versionadded:: 0.20.0
+
+        multicolumn_format : str, default 'l'
+            The alignment for multicolumns, similar to `column_format`
+            The default will be read from the config module.
+
+            .. versionadded:: 0.20.0
+
+        multirow : boolean, default False
+            Use \multirow to enhance MultiIndex rows.
+            Requires adding a \\usepackage{multirow} to your LaTeX preamble.
+            Will print centered labels (instead of top-aligned)
+            across the contained rows, separating groups via clines.
+            The default will be read from the pandas config module.
+
+            .. versionadded:: 0.20.0
+            """
+
+    @Substitution(header='Write out column names. If a list of string is given, \
+it is assumed to be aliases for the column names.')
+    @Appender(_shared_docs['to_latex'] % _shared_doc_kwargs)
+    def to_latex(self, buf=None, columns=None, col_space=None, header=True,
+                 index=True, na_rep='NaN', formatters=None, float_format=None,
+                 sparsify=None, index_names=True, bold_rows=True,
+                 column_format=None, longtable=None, escape=None,
+                 encoding=None, decimal='.', multicolumn=None,
+                 multicolumn_format=None, multirow=None):
+        # Get defaults from the pandas config
+        if self.ndim == 1:
+            self = self.to_frame()
+        if longtable is None:
+            longtable = config.get_option("display.latex.longtable")
+        if escape is None:
+            escape = config.get_option("display.latex.escape")
+        if multicolumn is None:
+            multicolumn = config.get_option("display.latex.multicolumn")
+        if multicolumn_format is None:
+            multicolumn_format = config.get_option(
+                "display.latex.multicolumn_format")
+        if multirow is None:
+            multirow = config.get_option("display.latex.multirow")
+
+        formatter = DataFrameFormatter(self, buf=buf, columns=columns,
+                                       col_space=col_space, na_rep=na_rep,
+                                       header=header, index=index,
+                                       formatters=formatters,
+                                       float_format=float_format,
+                                       bold_rows=bold_rows,
+                                       sparsify=sparsify,
+                                       index_names=index_names,
+                                       escape=escape, decimal=decimal)
+        formatter.to_latex(column_format=column_format, longtable=longtable,
+                           encoding=encoding, multicolumn=multicolumn,
+                           multicolumn_format=multicolumn_format,
+                           multirow=multirow)
+
+        if buf is None:
+            return formatter.buf.getvalue()
+
     # ----------------------------------------------------------------------
     # Fancy Indexing
 

pandas/tests/io/formats/test_to_latex.py

@@ -3,7 +3,7 @@
 import pytest
 
 import pandas as pd
-from pandas import DataFrame, compat
+from pandas import DataFrame, compat, Series
 from pandas.util import testing as tm
 from pandas.compat import u
 import codecs
@@ -491,3 +491,18 @@ def test_to_latex_decimal(self, frame):
 """
 
         assert withindex_result == withindex_expected
+
+    def test_to_latex_series(self):
+        s = Series(['a', 'b', 'c'])
+        withindex_result = s.to_latex()
+        withindex_expected = r"""\begin{tabular}{ll}
+\toprule
+{} &  0 \\
+\midrule
+0 &  a \\
+1 &  b \\
+2 &  c \\
+\bottomrule
+\end{tabular}
+"""
+        assert withindex_result == withindex_expected

pandas/tests/series/test_repr.py

@@ -8,7 +8,7 @@
 import numpy as np
 import pandas as pd
 
-from pandas import (Index, Series, DataFrame, date_range)
+from pandas import (Index, Series, DataFrame, date_range, option_context)
 from pandas.core.index import MultiIndex
 
 from pandas.compat import lrange, range, u
@@ -180,3 +180,21 @@ def test_timeseries_repr_object_dtype(self):
 
         ts2 = ts.iloc[np.random.randint(0, len(ts) - 1, 400)]
         repr(ts2).splitlines()[-1]
+
+    def test_latex_repr(self):
+        result = r"""\begin{tabular}{ll}
+\toprule
+{} &         0 \\
+\midrule
+0 &  $\alpha$ \\
+1 &         b \\
+2 &         c \\
+\bottomrule
+\end{tabular}
+"""
+        with option_context('display.latex.escape', False,
+                            'display.latex.repr', True):
+            s = Series([r'$\alpha$', 'b', 'c'])
+            assert result == s._repr_latex_()
+
+        assert s._repr_latex_() is None