.. _pylab_examples-spectrum_demo:

pylab_examples example code: spectrum_demo.py
=============================================



.. plot:: /home/tcaswell/source/p/matplotlib/doc/mpl_examples/pylab_examples/spectrum_demo.py

::

    import matplotlib.pyplot as plt
    import numpy as np
    
    
    np.random.seed(0)
    
    dt = 0.01
    Fs = 1/dt
    t = np.arange(0, 10, dt)
    nse = np.random.randn(len(t))
    r = np.exp(-t/0.05)
    
    cnse = np.convolve(nse, r)*dt
    cnse = cnse[:len(t)]
    s = 0.1*np.sin(2*np.pi*t) + cnse
    
    plt.subplot(3, 2, 1)
    plt.plot(t, s)
    
    plt.subplot(3, 2, 3)
    plt.magnitude_spectrum(s, Fs=Fs)
    
    plt.subplot(3, 2, 4)
    plt.magnitude_spectrum(s, Fs=Fs, scale='dB')
    
    plt.subplot(3, 2, 5)
    plt.angle_spectrum(s, Fs=Fs)
    
    plt.subplot(3, 2, 6)
    plt.phase_spectrum(s, Fs=Fs)
    
    plt.show()
    

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