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POPerformance issues using nested for loops for image processing
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copied!<p>I have code, shown <a href="https://github.com/wesleybowman/cgh/blob/master/cgh.py" rel="nofollow">here</a>, that makes a computer generated hologram given an initial image. The image that the program is currently using can be found in the in the <a href="https://github.com/wesleybowman/cgh" rel="nofollow">image directory</a>.</p> <p>My program takes approx. one minute to run, and that is for a 10x10 pixel A, that only has 14 spots that the nested for loops actually care about. The slow down is the in getComplexwave function:</p> <pre><code> def getComplexwave(): '''Iterate through every source point, and calculate the complex wave contribution at each sampling pixel on the film.''' for o in xrange(objPointShape): print o+1 for i in xrange(ipxShape): for j in xrange(ipyShape): dx=objectpoints[o][0] - ipx[0][i] dy=objectpoints[o][1] - ipy[0][j] dz=objectpoints[o][2] distance=np.sqrt(dx**2+dy**2+dz**2) complexwave=np.exp(1j*k*distance) hologram[i][j]=hologram[i][j]+complexwave </code></pre> <p>Can someone help me vectorize this, or at least make it to where it is faster? I am still fairly new to python.</p> <p>Also, any other suggestions to make the code better will be much appreciated! The output should look like <a href="http://imgur.com/a/YQ4Z9#1bW6g3J" rel="nofollow">this</a>.</p> <p><a href="http://pastebin.com/rwxvhhS0" rel="nofollow">The profiling information</a> for those who want it. Note that this is only the first ten, and it is sorted by internal time.</p>

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