Fix Excel header NaN

Author: Justine Kosinski

pandas/io/formats/excel.py

@@ -116,8 +116,8 @@ class CSSToExcelConverter:
  focusing on font styling, backgrounds, borders and alignment.
 
  Operates by first computing CSS styles in a fairly generic
- way (see :meth:`compute_css`) then determining Excel style
- properties from CSS properties (see :meth:`build_xlstyle`).
+ way (see :meth: `compute_css`) then determining Excel style
+ properties from CSS properties (see :meth: `build_xlstyle`).
 
  Parameters
  ----------
@@ -587,14 +587,15 @@ def __init__(
 
  def _format_value(self, val):
  if is_scalar(val) and missing.isna(val):
- val = self.na_rep
+ return self.na_rep
  elif is_float(val):
  if missing.isposinf_scalar(val):
- val = self.inf_rep
+ return self.inf_rep
  elif missing.isneginf_scalar(val):
- val = f"-{self.inf_rep}"
+ return f"-{self.inf_rep}"
  elif self.float_format is not None:
- val = float(self.float_format % val)
+ return float(self.float_format % val)
+
  if getattr(val, "tzinfo", None) is not None:
  raise ValueError(
  "Excel does not support datetimes with "
@@ -616,15 +617,25 @@ def _format_header_mi(self) -> Iterable[ExcelCell]:
 
  columns = self.columns
  merge_columns = self.merge_cells in {True, "columns"}
- level_strs = columns._format_multi(sparsify=merge_columns, include_names=False)
+ NBSP = "\u00a0"
+
+ fixed_levels = []
+ for lvl in range(columns.nlevels):
+ vals = columns.get_level_values(lvl)
+ fixed_levels.append(vals.fillna(NBSP))
+ fixed_columns = MultiIndex.from_arrays(fixed_levels, names=columns.names)
+
+ level_strs = fixed_columns._format_multi(
+ sparsify=merge_columns, include_names=False
+ )
  level_lengths = get_level_lengths(level_strs)
  coloffset = 0
  lnum = 0
 
  if self.index and isinstance(self.df.index, MultiIndex):
  coloffset = self.df.index.nlevels - 1
 
- for lnum, name in enumerate(columns.names):
+ for lnum, name in enumerate(fixed_columns.names):
  yield ExcelCell(
  row=lnum,
  col=coloffset,
@@ -633,7 +644,7 @@ def _format_header_mi(self) -> Iterable[ExcelCell]:
  )
 
  for lnum, (spans, levels, level_codes) in enumerate(
- zip(level_lengths, columns.levels, columns.codes, strict=True)
+ zip(level_lengths, fixed_columns.levels, fixed_columns.codes, strict=True)
  ):
  values = levels.take(level_codes)
  for i, span_val in spans.items():
@@ -657,7 +668,6 @@ def _format_header_mi(self) -> Iterable[ExcelCell]:
  def _format_header_regular(self) -> Iterable[ExcelCell]:
  if self._has_aliases or self.header:
  coloffset = 0
-
  if self.index:
  coloffset = 1
  if isinstance(self.df.index, MultiIndex):
@@ -673,7 +683,10 @@ def _format_header_regular(self) -> Iterable[ExcelCell]:
  )
  colnames = self.header
 
- for colindex, colname in enumerate(colnames):
+ NBSP = "\u00a0"
+ output_colnames = colnames.fillna(NBSP)
+
+ for colindex, colname in enumerate(output_colnames):
  yield CssExcelCell(
  row=self.rowcounter,
  col=colindex + coloffset,
@@ -687,15 +700,14 @@ def _format_header_regular(self) -> Iterable[ExcelCell]:
 
  def _format_header(self) -> Iterable[ExcelCell]:
  gen: Iterable[ExcelCell]
-
  if isinstance(self.columns, MultiIndex):
  gen = self._format_header_mi()
  else:
  gen = self._format_header_regular()
 
  gen2: Iterable[ExcelCell] = ()
 
- if self.df.index.names:
+ if self.df.index.names and self.header is not False:
  row = [x if x is not None else "" for x in self.df.index.names] + [
  ""
  ] * len(self.columns)
@@ -762,35 +774,25 @@ def _format_regular_rows(self) -> Iterable[ExcelCell]:
  def _format_hierarchical_rows(self) -> Iterable[ExcelCell]:
  if self._has_aliases or self.header:
  self.rowcounter += 1
-
  gcolidx = 0
-
  if self.index:
  index_labels = self.df.index.names
- # check for aliases
  if self.index_label and isinstance(
  self.index_label, (list, tuple, np.ndarray, Index)
  ):
  index_labels = self.index_label
-
- # MultiIndex columns require an extra row
- # with index names (blank if None) for
- # unambiguous round-trip, Issue #11328
  if isinstance(self.columns, MultiIndex):
  self.rowcounter += 1
-
- # if index labels are not empty go ahead and dump
  if com.any_not_none(*index_labels) and self.header is not False:
  for cidx, name in enumerate(index_labels):
  yield ExcelCell(self.rowcounter - 1, cidx, name, None)
 
  if self.merge_cells and self.merge_cells != "columns":
- # Format hierarchical rows as merged cells.
+ # Cette partie (pour merge_cells=True) est correcte
  level_strs = self.df.index._format_multi(
  sparsify=True, include_names=False
  )
  level_lengths = get_level_lengths(level_strs)
-
  for spans, levels, level_codes in zip(
  level_lengths,
  self.df.index.levels,
@@ -802,10 +804,8 @@ def _format_hierarchical_rows(self) -> Iterable[ExcelCell]:
  allow_fill=levels._can_hold_na,
  fill_value=levels._na_value,
  )
- # GH#60099
- if isinstance(values[0], Period):
+ if values.size > 0 and isinstance(values[0], Period):
  values = values.to_timestamp()
-
  for i, span_val in spans.items():
  mergestart, mergeend = None, None
  if span_val > 1:
@@ -824,15 +824,11 @@ def _format_hierarchical_rows(self) -> Iterable[ExcelCell]:
  mergeend=mergeend,
  )
  gcolidx += 1
-
  else:
- # Format hierarchical rows with non-merged values.
  for indexcolvals in zip(*self.df.index, strict=True):
  for idx, indexcolval in enumerate(indexcolvals):
- # GH#60099
  if isinstance(indexcolval, Period):
  indexcolval = indexcolval.to_timestamp()
-
  yield CssExcelCell(
  row=self.rowcounter + idx,
  col=gcolidx,
@@ -844,7 +840,6 @@ def _format_hierarchical_rows(self) -> Iterable[ExcelCell]:
  css_converter=self.style_converter,
  )
  gcolidx += 1
-
  yield from self._generate_body(gcolidx)
 
  @property
@@ -901,9 +896,7 @@ def write(
  write engine to use if writer is a path - you can also set this
  via the options ``io.excel.xlsx.writer``,
  or ``io.excel.xlsm.writer``.
-
  {storage_options}
-
  engine_kwargs: dict, optional
  Arbitrary keyword arguments passed to excel engine.
  """