axes_grid1 example code: demo_axes_grid.py

(Source code, png, pdf)

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


def get_demo_image():
    import numpy as np
    from matplotlib.cbook import get_sample_data
    f = get_sample_data("axes_grid/bivariate_normal.npy", asfileobj=False)
    z = np.load(f)
    # 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 i in range(4):
        im = grid[i].imshow(Z, extent=extent, interpolation="nearest")

    # 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 i in range(4):
        im = grid[i].imshow(Z, extent=extent, interpolation="nearest")
    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 i in range(4):
        im = grid[i].imshow(Z, extent=extent, interpolation="nearest")
        grid.cbar_axes[i].colorbar(im)

    for cax in grid.cbar_axes:
        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 i in range(4):
        im = grid[i].imshow(Z, extent=extent, interpolation="nearest",
                            vmin=limits[i][0], vmax=limits[i][1])
        grid.cbar_axes[i].colorbar(im)

    for i, cax in enumerate(grid.cbar_axes):
        cax.set_yticks((limits[i][0], limits[i][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])


if 1:
    F = plt.figure(1, (10.5, 2.5))

    F.subplots_adjust(left=0.05, right=0.95)

    demo_simple_grid(F)
    demo_grid_with_single_cbar(F)
    demo_grid_with_each_cbar(F)
    demo_grid_with_each_cbar_labelled(F)

    plt.draw()
    plt.show()

Keywords: python, matplotlib, pylab, example, codex (see Search examples)