.. _api-donut_demo:

api example code: donut_demo.py
===============================



.. plot:: /home/mandrake/rpm/BUILD/matplotlib-1.1.1/doc/mpl_examples/api/donut_demo.py

::

    import numpy as np
    import matplotlib.path as mpath
    import matplotlib.patches as mpatches
    import matplotlib.pyplot as plt
    
    def wise(v):
        if v == 1:
            return "CCW"
        else:
            return "CW"
    
    def make_circle(r):
        t = np.arange(0, np.pi * 2.0, 0.01)
        t = t.reshape((len(t), 1))
        x = r * np.cos(t)
        y = r * np.sin(t)
        return np.hstack((x, y))
    
    Path = mpath.Path
    
    fig = plt.figure()
    ax = fig.add_subplot(111)
    
    inside_vertices = make_circle(0.5)
    outside_vertices = make_circle(1.0)
    codes = np.ones(len(inside_vertices), dtype=mpath.Path.code_type) * mpath.Path.LINETO
    codes[0] = mpath.Path.MOVETO
    
    for i, (inside, outside) in enumerate(((1, 1), (1, -1), (-1, 1), (-1, -1))):
        # Concatenate the inside and outside subpaths together, changing their
        # order as needed
        vertices = np.concatenate((outside_vertices[::outside],
                                   inside_vertices[::inside]))
        # Shift the path
        vertices[:, 0] += i * 2.5
        # The codes will be all "LINETO" commands, except for "MOVETO"s at the
        # beginning of each subpath
        all_codes = np.concatenate((codes, codes))
        # Create the Path object
        path = mpath.Path(vertices, all_codes)
        # Add plot it
        patch = mpatches.PathPatch(path, facecolor='#885500', edgecolor='black')
        ax.add_patch(patch)
    
        ax.annotate("Outside %s,\nInside %s" % (wise(outside), wise(inside)),
                    (i * 2.5, -1.5), va="top", ha="center")
    
    ax.set_xlim(-2,10)
    ax.set_ylim(-3,2)
    ax.set_title('Mmm, donuts!')
    ax.set_aspect(1.0)
    plt.show()
    
    
    

Keywords: python, matplotlib, pylab, example, codex (see :ref:`how-to-search-examples`)