It's good to have some extra references for NumPy. Actually, it looks like exercising histogram in NunPy has gotten me past the difficulties with hist in matplotlib. I Is there a matplotlib or Pylab mailing list. It uses hist and looks very much like histogram, but has some parameters that I need to understand better. . -- Wayne Watson (Watson Adventures, Prop., Nevada City, CA) (121.015 Deg. W, 39.262 Deg. N) GMT-8 hr std. time) Obz Site: 39° 15' 7" N, 121° 2' 32" W, 2700 feet 350 350 350 350 350 350 350 350 350 350 Make the number famous. See 350.org The major event has passed, but keep the number alive. Web Page: <www.speckledwithstars.net/>