Excellent. Thank you very much!

On 6/10/07, Jake Emerson <[EMAIL PROTECTED]> wrote:

 The python imaging library is pretty good for this kind of thing.

http://www.pythonware.com/library/pil/handbook/

Here's an (untested) example. Hope it helps.

Jake


#!/usr/bin/env python

from pylab import scatter, save
import Image

#get the background image, and find out how big it is
im_bg = Image.open("background.png")
bg_width, bg_height = im.size

 #make a white canvas on which to paste the background image and the
scatter plot
#this will allow you to, say, have the x- and y-axis values fall outside
of the background image's limits
im_canvas = Image.new("RGBA", (bg_width+60, bg_height+60), (255, 255, 255,
0))

#create the scatter plot from x and y data with matplotlib
scatter(x, y, s=sizes, alpha=0.75)

#save the scatter plot, and then retrieve it for use in PIL, convert to
RGBA so that alpha levels will work
#there is probably a better way to do this with gcf() or gci()...
savefig("scatter_plot.png")
im_scatter = Image.open("scatter_plot.png").convert("RGBA")

#resize the scatter image to make it fit nice
im_scatter.resize((bg_width+10, bg_height+10))

#bring all of the images together by pasting them onto the white canvas,
use the overlayed image as the mask (third element)
im_canvas.paste(im_bg, (30, 30), im_bg)                   #play around
with the paste locations (30, 30)
im_canvas.paste(im_scatter, (10, 30), im_scatter)      #these won't be
perfect the first time (10, 30)

#save it
im_canvas.save("combo_image.png")




 ------------------------------
 *From:* __ [mailto:[EMAIL PROTECTED]
*Sent:* Sunday, June 10, 2007 5:22 PM
*To:* [email protected]
*Subject:* [Matplotlib-users] Simple scatter plot over an image

Hello,

I'm trying to plot a simple list of x/y coords over an image (.png). I can
show the image, or plot the data, but cannot find a way to layer one over
the other. I would greatly appreciate someone pointing me in the right
direction. Thanks.

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