Mercurial > pylearn

annotate cost.py @ 436:d7ed780364b3

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author Olivier Breuleux <breuleuo@iro.umontreal.ca>
date Wed, 06 Aug 2008 19:39:14 -0400
parents 0f366ecb11ee
children 45879c1ecde7
rev   line source
413
f63dfb0ac7dc Added cost functions
Joseph Turian <turian@iro.umontreal.ca>
parents:
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1 """
f63dfb0ac7dc Added cost functions
Joseph Turian <turian@iro.umontreal.ca>
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2 Cost functions.
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Joseph Turian <turian@iro.umontreal.ca>
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3 """
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4
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319bf28c2dd5 Small bugfix
Joseph Turian <turian@iro.umontreal.ca>
parents: 413
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5 import theano.tensor as T
319bf28c2dd5 Small bugfix
Joseph Turian <turian@iro.umontreal.ca>
parents: 413
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6
413
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Joseph Turian <turian@iro.umontreal.ca>
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7 def quadratic(target, output, axis=1):
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Joseph Turian <turian@iro.umontreal.ca>
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8 return T.mean(T.sqr(target - output), axis)
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Joseph Turian <turian@iro.umontreal.ca>
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9
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Joseph Turian <turian@iro.umontreal.ca>
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10 def cross_entropy(target, output, axis=1):
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0f366ecb11ee log2->log in cost
Olivier Breuleux <breuleuo@iro.umontreal.ca>
parents: 415
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11 return -T.mean(target * T.log(output) + (1 - target) * T.log(1 - output), axis=axis)