show test scripts for animated figures with blit, imshow, axis and text in Matplotlib

ax.xaxis.py

#!/usr/bin/env python3

import matplotlib.animation as animation
import matplotlib.pyplot as plt
import numpy as np

# https://stackoverflow.com/a/30860027/242583
# patch for ax.xaxis
# 1. ax.xaxis.set_animated(True)
# 2. add ax.xaxis to the returning list of update function
def _blit_draw(self, artists, bg_cache):
    # Handles blitted drawing, which renders only the artists given instead
    # of the entire figure.
    updated_ax = []
    for a in artists:
        # If we haven't cached the background for this axes object, do
        # so now. This might not always be reliable, but it's an attempt
        # to automate the process.
        if a.axes not in bg_cache:
            # bg_cache[a.axes] = a.figure.canvas.copy_from_bbox(a.axes.bbox)
            # change here
            bg_cache[a.axes] = a.figure.canvas.copy_from_bbox(a.axes.figure.bbox)
        a.axes.draw_artist(a)
        updated_ax.append(a.axes)

    # After rendering all the needed artists, blit each axes individually.
    for ax in set(updated_ax):
        # and here
        # ax.figure.canvas.blit(ax.bbox)
        ax.figure.canvas.blit(ax.figure.bbox)

# MONKEY PATCH!!
animation.Animation._blit_draw = _blit_draw


def update(data, axes, im):

    im.set_data(data)

    ax = axes[1]
    xlabels = [str(i) for i in np.random.randint(100, size=4)]
    ax.xaxis.set_ticklabels(xlabels)

    return axes + [ax.xaxis]


def main():

    fig = plt.figure()
    ax = plt.axes([0.1, 0.2, 0.8, 0.7])

    frames = []
    data = np.arange(64).reshape(8, 8)
    data = data + np.transpose(data)
    data %= 8
    frames.append(data / 7)
    for i in range(8 - 1):
        data = data + 1
        data %= 8
        frames.append(data / 7)

    IMSHOW_OPTS = {
        'aspect': 'auto',
        'cmap': plt.get_cmap('Purples'),
        'interpolation': 'none',
        'animated': True,
    }
    im = ax.imshow(frames[1], **IMSHOW_OPTS)
    imdata = im
    ax.grid(axis='x', which='major')

    ax = plt.axes([0.1, 0.1, 0.8, 0.05])
    data = np.arange(256)
    data = np.vstack((data, data))
    IMSHOW_OPTS['cmap'] = plt.get_cmap('gray')
    im = ax.imshow(data, **IMSHOW_OPTS)
    ax.set_xticks(np.arange(0, 256, 64))
    ax.set_xlim(left=0.0, right=255.0)
    ax.grid(axis='x', which='major')
    ax.xaxis.set_animated(True)

    animation.FuncAnimation(
        fig,
        update,
        frames=frames,
        fargs=(fig.get_axes(), imdata, ),
        interval=500,
        blit=True,
    )

    plt.show()


main()

basic.py

#!/usr/bin/env python3

import matplotlib.animation as animation
import matplotlib.pyplot as plt
import numpy as np


def update(data, ax, im):

    im.set_data(data)

    return [ax]


def main():

    fig = plt.figure()
    ax = plt.axes([0.1, 0.1, 0.8, 0.8])

    frames = []
    data = np.arange(64).reshape(8, 8)
    data = data + np.transpose(data)
    data %= 8
    frames.append(data / 7)
    for i in range(8 - 1):
        data = data + 1
        data %= 8
        frames.append(data / 7)

    IMSHOW_OPTS = {
        'aspect': 'auto',
        'cmap': plt.get_cmap('Purples'),
        'interpolation': 'none',
        'animated': True,
    }
    im = ax.imshow(frames[1], **IMSHOW_OPTS)
    ax.grid(axis='x', which='major')

    animation.FuncAnimation(
        fig,
        update,
        frames=frames,
        fargs=(ax, im, ),
        interval=500,
        blit=True,
    )

    plt.show()


main()

figtext.py

#!/usr/bin/env python3

import matplotlib.animation as animation
import matplotlib.pyplot as plt
import numpy as np

# https://stackoverflow.com/a/30860027/242583
# patch for ax.xaxis
# 1. ax.xaxis.set_animated(True)
# 2. add ax.xaxis to the returning list of update function
def _blit_draw(self, artists, bg_cache):
    # Handles blitted drawing, which renders only the artists given instead
    # of the entire figure.
    updated_ax = []
    for a in artists:
        # If we haven't cached the background for this axes object, do
        # so now. This might not always be reliable, but it's an attempt
        # to automate the process.
        if a.axes not in bg_cache:
            # bg_cache[a.axes] = a.figure.canvas.copy_from_bbox(a.axes.bbox)
            # change here
            bg_cache[a.axes] = a.figure.canvas.copy_from_bbox(a.axes.figure.bbox)
        a.axes.draw_artist(a)
        updated_ax.append(a.axes)

    # After rendering all the needed artists, blit each axes individually.
    for ax in set(updated_ax):
        # and here
        # ax.figure.canvas.blit(ax.bbox)
        ax.figure.canvas.blit(ax.figure.bbox)

# MONKEY PATCH!!
animation.Animation._blit_draw = _blit_draw


def update(data, axes, im, text):

    im.set_data(data)

    ax = axes[1]
    xlabels = [str(i) for i in np.random.randint(100, size=4)]
    ax.xaxis.set_ticklabels(xlabels)

    text.set_text(str(np.random.randint(100)))

    return axes + [ax.xaxis, text]


def main():

    fig = plt.figure()
    ax = plt.axes([0.1, 0.2, 0.8, 0.7])

    frames = []
    data = np.arange(64).reshape(8, 8)
    data = data + np.transpose(data)
    data %= 8
    frames.append(data / 7)
    for i in range(8 - 1):
        data = data + 1
        data %= 8
        frames.append(data / 7)

    IMSHOW_OPTS = {
        'aspect': 'auto',
        'cmap': plt.get_cmap('Purples'),
        'interpolation': 'none',
        'animated': True,
    }
    im = ax.imshow(frames[1], **IMSHOW_OPTS)
    imdata = im
    ax.grid(axis='x', which='major')

    ax = plt.axes([0.1, 0.1, 0.8, 0.05])
    data = np.arange(256)
    data = np.vstack((data, data))
    IMSHOW_OPTS['cmap'] = plt.get_cmap('gray')
    im = ax.imshow(data, **IMSHOW_OPTS)
    ax.set_xticks(np.arange(0, 256, 64))
    ax.set_xlim(left=0.0, right=255.0)
    ax.grid(axis='x', which='major')
    ax.xaxis.set_animated(True)

    # not fig.text, animation can only support Artist belonging to Axes
    text = ax.text(0.95, 0.05, 'JUST STARTED', transform=fig.transFigure,
                    horizontalalignment='right', verticalalignment='center')
    text.set_animated(True)

    animation.FuncAnimation(
        fig,
        update,
        frames=frames,
        fargs=(fig.get_axes(), imdata, text),
        interval=500,
        blit=True,
    )

    plt.show()


main()