Method _do_layout

lib/matplotlib/figure.py:2101–2194

Recursively do the mosaic. Parameters ---------- gs : GridSpec mosaic : 2D object array The input converted to a 2D array for this level. unique_ids : tuple The identified scalar labels at this

(gs, mosaic, unique_ids, nested)

            return tuple(unique_ids), nested

        def _do_layout(gs, mosaic, unique_ids, nested):
            """
            Recursively do the mosaic.

            Parameters
            ----------
            gs : GridSpec
            mosaic : 2D object array
                The input converted to a 2D array for this level.
            unique_ids : tuple
                The identified scalar labels at this level of nesting.
            nested : dict[tuple[int, int]], 2D object array
                The identified nested mosaics, if any.

            Returns
            -------
            dict[label, Axes]
                A flat dict of all of the Axes created.
            """
            output = dict()

            # we need to merge together the Axes at this level and the Axes
            # in the (recursively) nested sub-mosaics so that we can add
            # them to the figure in the "natural" order if you were to
            # ravel in c-order all of the Axes that will be created
            #
            # This will stash the upper left index of each object (axes or
            # nested mosaic) at this level
            this_level = dict()

            # go through the unique keys,
            for name in unique_ids:
                # sort out where each axes starts/ends
                index = np.argwhere(mosaic == name)
                start_row, start_col = np.min(index, axis=0)
                end_row, end_col = np.max(index, axis=0) + 1
                # and construct the slice object
                slc = (slice(start_row, end_row), slice(start_col, end_col))
                # some light error checking
                if (mosaic[slc] != name).any():
                    raise ValueError(
                        f"While trying to layout\n{mosaic!r}\n"
                        f"we found that the label {name!r} specifies a "
                        "non-rectangular or non-contiguous area.")
                # and stash this slice for later
                this_level[(start_row, start_col)] = (name, slc, 'axes')

            # do the same thing for the nested mosaics (simpler because these
            # cannot be spans yet!)
            for (j, k), nested_mosaic in nested.items():
                this_level[(j, k)] = (None, nested_mosaic, 'nested')

            # now go through the things in this level and add them
            # in order left-to-right top-to-bottom
            for key in sorted(this_level):
                name, arg, method = this_level[key]
                # we are doing some hokey function dispatch here based
                # on the 'method' string stashed above to sort out if this