.. _pylab_examples-integral_demo:

pylab_examples example code: integral_demo.py
=============================================



.. plot:: /media/TOSHI/temp/numpy_scipy_matplotlib/matplotlib/matplotlib-1.1.1~rc2/doc/mpl_examples/pylab_examples/integral_demo.py

::

    #!/usr/bin/env python
    
    # implement the example graphs/integral from pyx
    from pylab import *
    from matplotlib.patches import Polygon
    
    def func(x):
        return (x-3)*(x-5)*(x-7)+85
    
    ax = subplot(111)
    
    a, b = 2, 9 # integral area
    x = arange(0, 10, 0.01)
    y = func(x)
    plot(x, y, linewidth=1)
    
    # make the shaded region
    ix = arange(a, b, 0.01)
    iy = func(ix)
    verts = [(a,0)] + zip(ix,iy) + [(b,0)]
    poly = Polygon(verts, facecolor='0.8', edgecolor='k')
    ax.add_patch(poly)
    
    text(0.5 * (a + b), 30,
         r"$\int_a^b f(x)\mathrm{d}x$", horizontalalignment='center',
         fontsize=20)
    
    axis([0,10, 0, 180])
    figtext(0.9, 0.05, 'x')
    figtext(0.1, 0.9, 'y')
    ax.set_xticks((a,b))
    ax.set_xticklabels(('a','b'))
    ax.set_yticks([])
    show()
    

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