.. _api-demo_affine_image: api example code: demo_affine_image.py ====================================== .. plot:: /home/tcaswell/source/my_source/matplotlib/doc/mpl_examples/api/demo_affine_image.py :: #!/usr/bin/env python """ For the backends that supports draw_image with optional affine transform (e.g., agg, ps backend), the image of the output should have its boundary matches the red rectangles. """ import numpy as np import matplotlib.cm as cm import matplotlib.mlab as mlab import matplotlib.pyplot as plt import matplotlib.transforms as mtransforms def get_image(): delta = 0.25 x = y = np.arange(-3.0, 3.0, delta) X, Y = np.meshgrid(x, y) Z1 = mlab.bivariate_normal(X, Y, 1.0, 1.0, 0.0, 0.0) Z2 = mlab.bivariate_normal(X, Y, 1.5, 0.5, 1, 1) Z = Z2 - Z1 # difference of Gaussians return Z def imshow_affine(ax, z, *kl, **kwargs): im = ax.imshow(z, *kl, **kwargs) x1, x2, y1, y2 = im.get_extent() im._image_skew_coordinate = (x2, y1) return im if 1: # image rotation fig, (ax1, ax2) = plt.subplots(1, 2) Z = get_image() im1 = imshow_affine(ax1, Z, interpolation='none', cmap=cm.jet, origin='lower', extent=[-2, 4, -3, 2], clip_on=True) trans_data2 = mtransforms.Affine2D().rotate_deg(30) + ax1.transData im1.set_transform(trans_data2) # display intended extent of the image x1, x2, y1, y2 = im1.get_extent() x3, y3 = x2, y1 ax1.plot([x1, x2, x2, x1, x1], [y1, y1, y2, y2, y1], "r--", lw=3, transform=trans_data2) ax1.set_xlim(-3, 5) ax1.set_ylim(-4, 4) # image skew im2 = ax2.imshow(Z, interpolation='none', cmap=cm.jet, origin='lower', extent=[-2, 4, -3, 2], clip_on=True) im2._image_skew_coordinate = (3, -2) plt.show() #plt.savefig("demo_affine_image") Keywords: python, matplotlib, pylab, example, codex (see :ref:`how-to-search-examples`)