[matplotlib] How to plot with plotfile?

I try to plot some data directly from a file but without any sucess so far...

from pylab import *

plotfile("test.txt",(0,1))

My test.txt is in the same folder and it's just

1 2 3
5 2 6
4 5 8

It returns

Traceback (most recent call last):
  File "C:\Documents and Settings\lafont.LNE\Bureau\plotfile.py", line
19, in <module>
    plotfile("test.txt",(0,1))
  File "C:\Python27\lib\site-packages\matplotlib\pyplot.py", line
1908, in plotfile
    yname, y = getname_val(cols[i])
  File "C:\Python27\lib\site-packages\matplotlib\pyplot.py", line
1880, in getname_val
    name = r.dtype.names[int(identifier)]
IndexError: tuple index out of range

I don't understand, I do the same as the example on the matplotlib
website, but it doesn't work