[Matplotlib-users] manipulating histogram data from hist function

[Philippe P. <phi...@gm...>]

Hello All,
  I am trying to produce a 2D density plot of a distribution and would
like to show the associated projection computed as histogram. I need
to perform an operation on the histogram to offset them.
  Right now I am doing this:

# plot my 2D distribution
   hexbin(x,y, cmap=cm.jet, bins='log',gridsize=151)
# compute the associated projection (I would like not to show them but
use the hist to get the histrgram data)
   ny, binsy, histoy = hist(y, bins=121, normed=1, histtype='step',
color='white')
   nx, binsx, histox = hist(x, bins=121, normed=1, histtype='step',
orientation='horizontal', color='white', alpha=0.0)
# manipulate the histogram data
   Nbinsx = binsx[:-1]
   Nbinsy = binsy[:-1]
# plot offset histogram
   plot (Nbinsx,nx-2.5,color='white')
   plot (ny-2.5, Nbinsy,color='white')

  I have two questions (my apology I am a novice with matplotlib):

1/  When executing the above script, I also display the histograms
generated when invoking "hist" (I tried to make this line tranparaent
by using alpha=0 but it did not work).
2/ can I directly manipulate the data within an histogram to
arbitrarily offset the histogram?

  Thank you for any suggestion. Best,  -- Philippe.