Method set_under

lib/matplotlib/colors.py:892–894

Set the color for low out-of-range values.

(self, color='k', alpha=None)

        pending=True,
        alternative="cmap.with_extremes(under=...) or Colormap(under=...)")
    def set_under(self, color='k', alpha=None):
        """Set the color for low out-of-range values."""
        self._set_extremes(under=(color, alpha))

    def get_over(self):
        """Get the color for high out-of-range values."""