ENH: Add centering option to DataFrame.to_latex

Author: parthava-adabala

doc/source/whatsnew/v3.0.0.rst

@@ -189,6 +189,7 @@ Other enhancements
 - :meth:`DataFrame.fillna` and :meth:`Series.fillna` can now accept ``value=None``; for non-object dtype the corresponding NA value will be used (:issue:`57723`)
 - :meth:`DataFrame.pivot_table` and :func:`pivot_table` now allow the passing of keyword arguments to ``aggfunc`` through ``**kwargs`` (:issue:`57884`)
 - :meth:`DataFrame.to_json` now encodes ``Decimal`` as strings instead of floats (:issue:`60698`)
+- :meth:`DataFrame.to_latex` and :meth:`.Styler.to_latex` now support a ``centering`` parameter to center the table in the LaTeX output (:issue:`62733`)
 - :meth:`Series.cummin` and :meth:`Series.cummax` now supports :class:`CategoricalDtype` (:issue:`52335`)
 - :meth:`Series.plot` now correctly handle the ``ylabel`` parameter for pie charts, allowing for explicit control over the y-axis label (:issue:`58239`)
 - :meth:`DataFrame.plot.scatter` argument ``c`` now accepts a column of strings, where rows with the same string are colored identically (:issue:`16827` and :issue:`16485`)

pandas/core/generic.py

@@ -3309,6 +3309,7 @@ def to_latex(
  caption: str | tuple[str, str] | None = ...,
  label: str | None = ...,
  position: str | None = ...,
+ centering: bool = ...,
  ) -> str: ...
 
  @overload
@@ -3336,6 +3337,7 @@ def to_latex(
  caption: str | tuple[str, str] | None = ...,
  label: str | None = ...,
  position: str | None = ...,
+ centering: bool = ...,
  ) -> None: ...
 
  @final
@@ -3363,6 +3365,7 @@ def to_latex(
  caption: str | tuple[str, str] | None = None,
  label: str | None = None,
  position: str | None = None,
+ centering: bool = False,
  ) -> str | None:
  r"""
  Render object to a LaTeX tabular, longtable, or nested table.
@@ -3469,6 +3472,10 @@ def to_latex(
  The LaTeX positional argument for tables, to be placed after
  ``\begin{}`` in the output.
 
+ centering : bool, default False
+ Whether to add the ``\centering`` command to center the table
+ inside the table environment.
+
  Returns
  -------
  str or None
@@ -3614,6 +3621,7 @@ def _wrap(x, alt_format_):
  if (multirow and isinstance(self.index, MultiIndex))
  else None,
  "bold_rows": bold_rows,
+ "centering": centering,
  }
 
  return self._to_latex_via_styler(

pandas/io/formats/style.py

@@ -637,6 +637,7 @@ def to_latex(
  multicol_align: str | None = ...,
  siunitx: bool = ...,
  environment: str | None = ...,
+ centering: bool = ...,
  encoding: str | None = ...,
  convert_css: bool = ...,
  ) -> None: ...
@@ -659,6 +660,7 @@ def to_latex(
  multicol_align: str | None = ...,
  siunitx: bool = ...,
  environment: str | None = ...,
+ centering: bool = ...,
  encoding: str | None = ...,
  convert_css: bool = ...,
  ) -> str: ...
@@ -680,6 +682,7 @@ def to_latex(
  multicol_align: str | None = None,
  siunitx: bool = False,
  environment: str | None = None,
+ centering: bool = False,
  encoding: str | None = None,
  convert_css: bool = False,
  ) -> str | None:
@@ -1227,6 +1230,7 @@ def to_latex(
  convert_css=convert_css,
  siunitx=siunitx,
  clines=clines,
+ centering=centering,
  )
 
  encoding = (

pandas/io/formats/style_render.py

@@ -226,12 +226,16 @@ def _render_latex(
  """
  Render a Styler in latex format
  """
+ centering = kwargs.pop("centering", False)
  d = self._render(sparse_index, sparse_columns, None, None)
  self._translate_latex(d, clines=clines)
- self.template_latex.globals["parse_wrap"] = _parse_latex_table_wrapping
+ self.template_latex.globals["parse_wrap"] = partial(
+ _parse_latex_table_wrapping, centering=centering
+ )
  self.template_latex.globals["parse_table"] = _parse_latex_table_styles
  self.template_latex.globals["parse_cell"] = _parse_latex_cell_styles
  self.template_latex.globals["parse_header"] = _parse_latex_header_span
+ d["centering"] = centering
  d.update(kwargs)
  return self.template_latex.render(**d)
 
@@ -2329,7 +2333,9 @@ def _translate(self, styler: StylerRenderer, d: dict):
  return d
 
 
-def _parse_latex_table_wrapping(table_styles: CSSStyles, caption: str | None) -> bool:
+def _parse_latex_table_wrapping(
+ table_styles: CSSStyles, caption: str | None, centering: bool = False
+) -> bool:
  """
  Indicate whether LaTeX {tabular} should be wrapped with a {table} environment.
 
@@ -2340,9 +2346,13 @@ def _parse_latex_table_wrapping(table_styles: CSSStyles, caption: str | None) ->
  IGNORED_WRAPPERS = ["toprule", "midrule", "bottomrule", "column_format"]
  # ignored selectors are included with {tabular} so do not need wrapping
  return (
- table_styles is not None
- and any(d["selector"] not in IGNORED_WRAPPERS for d in table_styles)
- ) or caption is not None
+ (
+ table_styles is not None
+ and any(d["selector"] not in IGNORED_WRAPPERS for d in table_styles)
+ )
+ or caption is not None
+ or centering
+ )
 
 
 def _parse_latex_table_styles(table_styles: CSSStyles, selector: str) -> str | None:

pandas/io/formats/templates/latex_longtable.tpl

@@ -29,6 +29,7 @@
 \label{{label}} \\
 {% endif %}
 {% endif %}
+{%- if centering %}\centering{% endif -%}
 {% set toprule = parse_table(table_styles, 'toprule') %}
 {% if toprule is not none %}
 \{{toprule}}

pandas/io/formats/templates/latex_table.tpl

@@ -9,6 +9,7 @@
 {% if position_float is not none%}
 \{{position_float}}
 {% endif %}
+{%- if centering %}\centering{% endif -%}
 {% if caption and caption is string %}
 \caption{% raw %}{{% endraw %}{{caption}}{% raw %}}{% endraw %}
 

pandas/tests/io/formats/test_to_latex.py

@@ -182,6 +182,30 @@ def test_to_latex_midrule_location(self):
  )
  assert result == expected
 
+ def test_to_latex_centering(self):
+ # test for \centering command #GH ENH #62733
+ df = DataFrame({"a": [1], "b": [2]})
+
+ # test with DataFrame.to_latex (centering=True)
+ latex_centered = df.to_latex(centering=True)
+ assert r"\centering" in latex_centered
+ # test with DataFrame.to_latex (centering=False)
+ latex_default = df.to_latex(centering=False)
+ assert r"\centering" not in latex_default
+ # test with DataFrame.to_latex with longtable (centering=True)
+ latex_long_centered = df.to_latex(centering=True, longtable=True)
+ assert r"\centering" in latex_long_centered
+ # test with DataFrame.to_latex with longtable (centering=False)
+ latex_long_default = df.to_latex(centering=False, longtable=True)
+ assert r"\centering" not in latex_long_default
+ # test with Styler.to_latex (centering=True)
+ styler = df.style
+ latex_styler_centered = styler.to_latex(centering=True)
+ assert r"\centering" in latex_styler_centered
+ # test with Styler.to_latex (centering=False)
+ latex_styler_default = styler.to_latex(centering=False)
+ assert r"\centering" not in latex_styler_default
+
 
 class TestToLatexLongtable:
  def test_to_latex_empty_longtable(self):