Mercurial > pylearn

annotate cost.py @ 419:43d9aa93934e

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added other_ops.py to nnet_ops; added basic tests, no docs.
author James Bergstra <bergstrj@iro.umontreal.ca>
date Mon, 14 Jul 2008 16:48:02 -0400
parents 319bf28c2dd5
children 0f366ecb11ee
rev   line source
413
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Joseph Turian <turian@iro.umontreal.ca>
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1 """
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2 Cost functions.
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3 """
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4
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Joseph Turian <turian@iro.umontreal.ca>
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5 import theano.tensor as T
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6
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7 def quadratic(target, output, axis=1):
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8 return T.mean(T.sqr(target - output), axis)
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9
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10 def cross_entropy(target, output, axis=1):
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11 return -T.mean(target * T.log2(output) + (1 - target) * T.log2(1 - output), axis=axis)