matplotlib.py 文件源码

def _get_cmap_data(data, kwargs):
    """Get normalized values to be used with a colormap.

    Parameters
    ----------
    data : array_like
    cmap_min : Optional[float] or "min"
        By default 0. If "min", minimum value of the data.
    cmap_max : Optional[float]
        By default, maximum value of the data
    cmap_normalize : str or colors.Normalize

    Returns
    -------
    normalizer : colors.Normalize
    normalized_data : array_like
    """
    norm = kwargs.pop("cmap_normalize", None)
    if norm == "log":
        cmap_max = kwargs.pop("cmap_max", data.max())
        cmap_min = kwargs.pop("cmap_min", data[data > 0].min())
        norm = colors.LogNorm(cmap_min, cmap_max)
    elif not norm:
        cmap_max = kwargs.pop("cmap_max", data.max())
        cmap_min = kwargs.pop("cmap_min", 0)
        if cmap_min == "min":
            cmap_min = data.min()
        norm = colors.Normalize(cmap_min, cmap_max, clip=True)
    return norm, norm(data)