.. _units-ellipse_with_units:

units example code: ellipse_with_units.py
=========================================



.. plot:: /home/mandrake/rpm/BUILD/matplotlib-1.1.1/doc/mpl_examples/units/ellipse_with_units.py

::

    """
    Compare the ellipse generated with arcs versus a polygonal approximation
    """
    from basic_units import cm
    import numpy as npy
    from matplotlib import patches
    from pylab import figure, show
    
    xcenter, ycenter = 0.38*cm, 0.52*cm
    #xcenter, ycenter = 0., 0.
    width, height = 1e-1*cm, 3e-1*cm
    angle = -30
    
    theta = npy.arange(0.0, 360.0, 1.0)*npy.pi/180.0
    x = 0.5 * width * npy.cos(theta)
    y = 0.5 * height * npy.sin(theta)
    
    rtheta = angle*npy.pi/180.
    R = npy.array([
        [npy.cos(rtheta),  -npy.sin(rtheta)],
        [npy.sin(rtheta), npy.cos(rtheta)],
        ])
    
    
    x, y = npy.dot(R, npy.array([x, y]))
    x += xcenter
    y += ycenter
    
    fig = figure()
    ax = fig.add_subplot(211, aspect='auto')
    ax.fill(x, y, alpha=0.2, facecolor='yellow', edgecolor='yellow', linewidth=1, zorder=1)
    
    e1 = patches.Ellipse((xcenter, ycenter), width, height,
                 angle=angle, linewidth=2, fill=False, zorder=2)
    
    ax.add_patch(e1)
    
    ax = fig.add_subplot(212, aspect='equal')
    ax.fill(x, y, alpha=0.2, facecolor='green', edgecolor='green', zorder=1)
    e2 = patches.Ellipse((xcenter, ycenter), width, height,
                 angle=angle, linewidth=2, fill=False, zorder=2)
    
    
    ax.add_patch(e2)
    
    #fig.savefig('ellipse_compare.png')
    fig.savefig('ellipse_compare')
    
    fig = figure()
    ax = fig.add_subplot(211, aspect='auto')
    ax.fill(x, y, alpha=0.2, facecolor='yellow', edgecolor='yellow', linewidth=1, zorder=1)
    
    e1 = patches.Arc((xcenter, ycenter), width, height,
                 angle=angle, linewidth=2, fill=False, zorder=2)
    
    ax.add_patch(e1)
    
    ax = fig.add_subplot(212, aspect='equal')
    ax.fill(x, y, alpha=0.2, facecolor='green', edgecolor='green', zorder=1)
    e2 = patches.Arc((xcenter, ycenter), width, height,
                 angle=angle, linewidth=2, fill=False, zorder=2)
    
    
    ax.add_patch(e2)
    
    #fig.savefig('arc_compare.png')
    fig.savefig('arc_compare')
    
    show()
    

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