Python: plotting multiple plots in the same window

问题

I am trying to use what I learned from plotting multiple plots but whith offset ranges python, but I can't seem to make the appropriate adjustments for my Legendre plotting code:

import numpy as np
import pylab
from numpy.polynomial.legendre import leggauss, legval


def f(x):
    if 0 <= x <= 1:
        return 1
    if -1 <= x <= 0:
        return -1


f = np.vectorize(f)

deg = 1000
x, w = leggauss(deg)  #  len(x) == deg
L = np.polynomial.legendre.legval(x, np.identity(deg))
integral = (L * (f(x) * w)[None,:]).sum(axis=1)
xx = np.linspace(-1, 1, 500000)
csum = []


for N in [5, 15, 25, 51, 97]:
    c = (np.arange(1, N) + 0.5) * integral[1:N]
    clnsum = (c[:,None] * L[1:N,:]).sum(axis = 0)
    csum.append(clnsum)


fig = pylab.figure()
ax = fig.add_subplot(111)


for i in csum:
    ax.plot(x, csum[i])


pylab.xlim((-1, 1))
pylab.ylim((-1.25, 1.25))
pylab.plot([0, 1], [1, 1], 'k')
pylab.plot([-1, 0], [-1, -1], 'k')
pylab.show()

I am using csum to hold each iteration of clnsum for N = 5, 15, 25, 51, 97. Then I want to plot each stored clnsum, but I believe this is where the problem is occurring.

I believe

for i in csum:

is the correct set up but ax.plot(x, csum[i]) must be the wrong way to plot each iteration. At least, this is what I believe, but maybe the whole set up is wrong or faulty.

How can I achieve the plotting of each clnsum for each N?