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annotate pylearn/dataset_ops/memo.py @ 832:67b92a42f86b

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added dataset_ops
author James Bergstra <bergstrj@iro.umontreal.ca>
date Fri, 16 Oct 2009 12:04:05 -0400
parents
children 7ccce98da2b6
rev   line source
832
67b92a42f86b added dataset_ops
James Bergstra <bergstrj@iro.umontreal.ca>
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1 """Provide a decorator that caches expensive functions
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2 """
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3 import logging
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4 _logger = logging.getLogger(__file__)
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5 info = _logger.info
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6 def infop(*args):
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7 info(' '.join(str(a) for a in args))
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8
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9 def memo(f):
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10 #TODO: support kwargs to rval. This requires looking up the names of f's parameters to
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11 # construct a proper key.
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12
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13 #TODO: use weak references instead of a normal dict so that the cache doesn't prevent
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14 # garbage collection
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15 cache = {}
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16 def rval(*args):
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17 if args not in cache:
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18 cache[args] = f(*args)
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19 return cache[args]
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20 rval.__name__ = 'memo@%s'%f.__name__
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21 return rval
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22