.. _animation-histogram: animation example code: histogram.py ==================================== [`source code `_] :: """ This example shows how to use a path patch to draw a bunch of rectangles for an animated histogram """ import numpy as np import matplotlib.pyplot as plt import matplotlib.patches as patches import matplotlib.path as path import matplotlib.animation as animation fig, ax = plt.subplots() # histogram our data with numpy data = np.random.randn(1000) n, bins = np.histogram(data, 100) # get the corners of the rectangles for the histogram left = np.array(bins[:-1]) right = np.array(bins[1:]) bottom = np.zeros(len(left)) top = bottom + n nrects = len(left) # here comes the tricky part -- we have to set up the vertex and path # codes arrays using moveto, lineto and closepoly # for each rect: 1 for the MOVETO, 3 for the LINETO, 1 for the # CLOSEPOLY; the vert for the closepoly is ignored but we still need # it to keep the codes aligned with the vertices nverts = nrects*(1+3+1) verts = np.zeros((nverts, 2)) codes = np.ones(nverts, int) * path.Path.LINETO codes[0::5] = path.Path.MOVETO codes[4::5] = path.Path.CLOSEPOLY verts[0::5,0] = left verts[0::5,1] = bottom verts[1::5,0] = left verts[1::5,1] = top verts[2::5,0] = right verts[2::5,1] = top verts[3::5,0] = right verts[3::5,1] = bottom barpath = path.Path(verts, codes) patch = patches.PathPatch(barpath, facecolor='green', edgecolor='yellow', alpha=0.5) ax.add_patch(patch) ax.set_xlim(left[0], right[-1]) ax.set_ylim(bottom.min(), top.max()) def animate(i): # simulate new data coming in data = np.random.randn(1000) n, bins = np.histogram(data, 100) top = bottom + n verts[1::5,1] = top verts[2::5,1] = top ani = animation.FuncAnimation(fig, animate, 100, repeat=False) plt.show() Keywords: python, matplotlib, pylab, example, codex (see :ref:`how-to-search-examples`)