Method _translate

pandas/io/formats/style_render.py:2239–2311

Mutate the render dictionary to allow for tooltips: - Add ``<span>`` HTML element to each data cells ``display_value``. Ignores headers. - Add table level CSS styles to control pseudo classes. Parameters ---------- styler_data : DataFrame

(self, styler: StylerRenderer, d: dict)

        ]

    def _translate(self, styler: StylerRenderer, d: dict):
        """
        Mutate the render dictionary to allow for tooltips:

        - Add ``<span>`` HTML element to each data cells ``display_value``. Ignores
          headers.
        - Add table level CSS styles to control pseudo classes.

        Parameters
        ----------
        styler_data : DataFrame
            Underlying ``Styler`` DataFrame used for reindexing.
        uuid : str
            The underlying ``Styler`` uuid for CSS id.
        d : dict
            The dictionary prior to final render

        Returns
        -------
        render_dict : Dict
        """
        self.tt_data = self.tt_data.reindex_like(styler.data)
        if self.tt_data.empty:
            return d

        mask = (self.tt_data.isna()) | (self.tt_data.eq(""))  # empty string = no ttip
        # this conditional adds tooltips via pseudo css and <span> elements.
        if not self.as_title_attribute:
            name = self.class_name
            self.table_styles = [
                style
                for sublist in [
                    self._pseudo_css(
                        styler.uuid, name, i, j, str(self.tt_data.iloc[i, j])
                    )
                    for i in range(len(self.tt_data.index))
                    for j in range(len(self.tt_data.columns))
                    if not (
                        mask.iloc[i, j]
                        or i in styler.hidden_rows
                        or j in styler.hidden_columns
                    )
                ]
                for style in sublist
            ]

            # add span class to every cell since there is at least 1 non-empty tooltip
            if self.table_styles:
                for row in d["body"]:
                    for item in row:
                        if item["type"] == "td":
                            item["display_value"] = (
                                str(item["display_value"])
                                + f'<span class="{self.class_name}"></span>'
                            )
                d["table_styles"].extend(self._class_styles)
                d["table_styles"].extend(self.table_styles)
        # this conditional adds tooltips as extra "title" attribute on a <td> element