ENH: multirow naive implementation Styler.to_latex part1

doc/source/whatsnew/v1.4.0.rst

@@ -78,6 +78,7 @@ Styler
   - :meth:`.Styler.to_html` introduces keyword arguments ``sparse_index``, ``sparse_columns``, ``bold_headers``, ``caption`` (:issue:`41946`, :issue:`43149`).
   - Keyword argument ``level`` is added to :meth:`.Styler.hide_index` and :meth:`.Styler.hide_columns` for optionally controlling hidden levels in a MultiIndex (:issue:`25475`)
   - Global options have been extended to configure default ``Styler`` properties including formatting and encoding and mathjax options and LaTeX (:issue:`41395`)
+  - Naive sparsification is now possible for LaTeX without the multirow package (:issue:`43369`)
 
 Formerly Styler relied on ``display.html.use_mathjax``, which has now been replaced by ``styler.html.mathjax``.
 

pandas/core/config_init.py

@@ -888,7 +888,7 @@ def register_converter_cb(key):
         "latex.multirow_align",
         "c",
         styler_multirow_align,
-        validator=is_one_of_factory(["c", "t", "b"]),
+        validator=is_one_of_factory(["c", "t", "b", "naive"]),
     )
 
     cf.register_option(

pandas/io/formats/style.py

@@ -520,10 +520,13 @@ def to_latex(
             Whether to sparsify the display of a hierarchical index. Setting to False
             will display each explicit level element in a hierarchical key for each
             column. Defaults to ``pandas.options.styler.sparse.columns`` value.
-        multirow_align : {"c", "t", "b"}, optional
+        multirow_align : {"c", "t", "b", "naive"}, optional
             If sparsifying hierarchical MultiIndexes whether to align text centrally,
-            at the top or bottom. If not given defaults to
-            ``pandas.options.styler.latex.multirow_align``
+            at the top or bottom using the multirow package. If not given defaults to
+            ``pandas.options.styler.latex.multirow_align``. If "naive" is given renders
+            without multirow.
+
+            .. versionchanged:: 1.4.0
         multicol_align : {"r", "c", "l"}, optional
             If sparsifying hierarchical MultiIndex columns whether to align text at
             the left, centrally, or at the right. If not given defaults to

pandas/io/formats/style_render.py

@@ -1413,6 +1413,8 @@ def _parse_latex_header_span(
             colspan = int(colspan[: colspan.find('"')])
             return f"\\multicolumn{{{colspan}}}{{{multicol_align}}}{{{display_val}}}"
         elif 'rowspan="' in attrs:
+            if multirow_align == "naive":
+                return display_val
             rowspan = attrs[attrs.find('rowspan="') + 9 :]
             rowspan = int(rowspan[: rowspan.find('"')])
             return f"\\multirow[{multirow_align}]{{{rowspan}}}{{*}}{{{display_val}}}"

pandas/tests/io/formats/style/test_to_latex.py

@@ -242,6 +242,25 @@ def test_multiindex_row(df):
     assert expected == s.to_latex(sparse_index=False)
 
 
+def test_multirow_naive(df):
+    ridx = MultiIndex.from_tuples([("A", "a"), ("A", "b"), ("B", "c")])
+    df.loc[2, :] = [2, -2.22, "de"]
+    df = df.astype({"A": int})
+    df.index = ridx
+    expected = dedent(
+        """\
+        \\begin{tabular}{llrrl}
+         &  & A & B & C \\\\
+        A & a & 0 & -0.61 & ab \\\\
+         & b & 1 & -1.22 & cd \\\\
+        B & c & 2 & -2.22 & de \\\\
+        \\end{tabular}
+        """
+    )
+    s = df.style.format(precision=2)
+    assert expected == s.to_latex(multirow_align="naive")
+
+
 def test_multiindex_row_and_col(df):
     cidx = MultiIndex.from_tuples([("Z", "a"), ("Z", "b"), ("Y", "c")])
     ridx = MultiIndex.from_tuples([("A", "a"), ("A", "b"), ("B", "c")])