to_numeric.py

非原创。很好的python例子

#!/usr/bin/env python
"""
Use backend agg to access the figure canvas as an RGB string and then
convert it to a Numeric array and pass the string it to PIL for
rendering
"""

from pylab import *
from matplotlib.backends.backend_agg import FigureCanvasAgg

plot([1,2,3])

canvas = get_current_fig_manager().canvas

agg = canvas.switch_backends(FigureCanvasAgg)
agg.draw()
s = agg.tostring_rgb()  

# get the width and the height to resize the matrix
l,b,w,h = agg.figure.bbox.get_bounds()
w, h = int(w), int(h)


X = fromstring(s, UInt8)
X.shape = h, w, 3

import Image
im = Image.fromstring( "RGB", (w,h), s)
im.show()