_utilities.py 文件源码

def plot_basemap(latitude, longitude, image, color_palette=None):
    # define basemap, color palette
    cmap, tiler = get_map_params(image, color_palette)

    # Find min/max coordinates to set extent
    lat_0, lat_1, lon_0, lon_1 = get_max_extent(latitude, longitude)

    # Automatically focus resolution
    max_span = max((abs(lat_1) - abs(lat_0)), (abs(lon_1) - abs(lon_0)))
    res = int(-1.4 * math.log1p(max_span) + 13)

    # initiate tiler projection
    ax = plt.axes(projection=tiler.crs)
    # Define extents of any plotted data
    ax.set_extent((lon_0, lon_1, lat_0, lat_1), ccrs.Geodetic())
    # add terrain background
    ax.add_image(tiler, res)

    return ax, cmap