# use masked arrays to plot a line with different colors by y-valueimport matplotlib.numerix.ma as mafrom matplotlib.numerix import logical_orfrom pylab import  plot, show, arange, sin, pit = arange(0.0, 2.0, 0.01)s = sin(2*pi*t)upper = 0.77lower = -0.77supper = ma.masked_where(s < upper, s)slower = ma.masked_where(s > lower, s)smiddle = ma.masked_where(logical_or(s<lower, s>upper), s)plot(t, slower, 'r', t, smiddle, 'b', t, supper, 'g')show()