Demo Axes Grid

Grid of 2x2 images with single or own colorbar.

from matplotlib import cbook
import matplotlib.pyplot as plt
from mpl_toolkits.axes_grid1 import ImageGrid


plt.rcParams["mpl_toolkits.legacy_colorbar"] = False


def get_demo_image():
    z = cbook.get_sample_data("axes_grid/bivariate_normal.npy", np_load=True)
    # z is a numpy array of 15x15
    return z, (-3, 4, -4, 3)


def demo_simple_grid(fig):
    """
    A grid of 2x2 images with 0.05 inch pad between images and only
    the lower-left axes is labeled.
    """
    grid = ImageGrid(fig, 141,  # similar to subplot(141)
                     nrows_ncols=(2, 2),
                     axes_pad=0.05,
                     label_mode="1",
                     )
    Z, extent = get_demo_image()
    for ax in grid:
        ax.imshow(Z, extent=extent)
    # This only affects axes in first column and second row as share_all=False.
    grid.axes_llc.set_xticks([-2, 0, 2])
    grid.axes_llc.set_yticks([-2, 0, 2])


def demo_grid_with_single_cbar(fig):
    """
    A grid of 2x2 images with a single colorbar
    """
    grid = ImageGrid(fig, 142,  # similar to subplot(142)
                     nrows_ncols=(2, 2),
                     axes_pad=0.0,
                     share_all=True,
                     label_mode="L",
                     cbar_location="top",
                     cbar_mode="single",
                     )

    Z, extent = get_demo_image()
    for ax in grid:
        im = ax.imshow(Z, extent=extent)
    grid.cbar_axes[0].colorbar(im)

    for cax in grid.cbar_axes:
        cax.toggle_label(False)

    # This affects all axes as share_all = True.
    grid.axes_llc.set_xticks([-2, 0, 2])
    grid.axes_llc.set_yticks([-2, 0, 2])


def demo_grid_with_each_cbar(fig):
    """
    A grid of 2x2 images. Each image has its own colorbar.
    """
    grid = ImageGrid(fig, 143,  # similar to subplot(143)
                     nrows_ncols=(2, 2),
                     axes_pad=0.1,
                     label_mode="1",
                     share_all=True,
                     cbar_location="top",
                     cbar_mode="each",
                     cbar_size="7%",
                     cbar_pad="2%",
                     )
    Z, extent = get_demo_image()
    for ax, cax in zip(grid, grid.cbar_axes):
        im = ax.imshow(Z, extent=extent)
        cax.colorbar(im)
        cax.toggle_label(False)

    # This affects all axes because we set share_all = True.
    grid.axes_llc.set_xticks([-2, 0, 2])
    grid.axes_llc.set_yticks([-2, 0, 2])


def demo_grid_with_each_cbar_labelled(fig):
    """
    A grid of 2x2 images. Each image has its own colorbar.
    """
    grid = ImageGrid(fig, 144,  # similar to subplot(144)
                     nrows_ncols=(2, 2),
                     axes_pad=(0.45, 0.15),
                     label_mode="1",
                     share_all=True,
                     cbar_location="right",
                     cbar_mode="each",
                     cbar_size="7%",
                     cbar_pad="2%",
                     )
    Z, extent = get_demo_image()

    # Use a different colorbar range every time
    limits = ((0, 1), (-2, 2), (-1.7, 1.4), (-1.5, 1))
    for ax, cax, vlim in zip(grid, grid.cbar_axes, limits):
        im = ax.imshow(Z, extent=extent, vmin=vlim[0], vmax=vlim[1])
        cb = cax.colorbar(im)
        cb.set_ticks((vlim[0], vlim[1]))

    # This affects all axes because we set share_all = True.
    grid.axes_llc.set_xticks([-2, 0, 2])
    grid.axes_llc.set_yticks([-2, 0, 2])


fig = plt.figure(figsize=(10.5, 2.5))
fig.subplots_adjust(left=0.05, right=0.95)

demo_simple_grid(fig)
demo_grid_with_single_cbar(fig)
demo_grid_with_each_cbar(fig)
demo_grid_with_each_cbar_labelled(fig)

plt.show()