Esempio n. 1
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    def make_chains(self, bias):
        """
        .. todo::

            WRITEME properly

        Make the shared variable representing a layer of
        the network for all negative chains

        for now units are initialized randomly based on their
        biases only
        """

        assert not self.use_cd

        b = bias.get_value(borrow=True)

        nhid ,= b.shape

        shape = (self.negative_chains, nhid)

        driver = self.rng.uniform(0.0, 1.0, shape)

        thresh = sigmoid_numpy(b)

        value = driver < thresh

        return sharedX(value)
Esempio n. 2
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 def set_biases(self, biases, recenter = False):
     self.b.set_value(biases)
     if recenter:
         assert self.center
         if self.pool_size != 1:
             raise NotImplementedError()
         self.offset.set_value(sigmoid_numpy(self.b.get_value()))
Esempio n. 3
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    def make_state(self, num_examples, numpy_rng):
        driver = numpy_rng.uniform(0.,1., (num_examples, self.nvis))
        on_prob = sigmoid_numpy(2. * self.ising_bias_numpy())
        sample = 2. * (driver < on_prob) - 1.

        rval = sharedX(sample, name = 'v_sample_shared')

        return rval
Esempio n. 4
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    def make_state(self, num_examples, numpy_rng):

        driver = numpy_rng.uniform(0., 1., (num_examples, self.nvis))
        mean = sigmoid_numpy(self.bias.get_value())
        sample = driver < mean

        rval = sharedX(sample, name='v_sample_shared')

        return rval
Esempio n. 5
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    def make_state(self, num_examples, numpy_rng):

        driver = numpy_rng.uniform(0.,1., (num_examples, self.nvis))
        mean = sigmoid_numpy(self.bias.get_value())
        sample = driver < mean

        rval = sharedX(sample, name = 'v_sample_shared')

        return rval
Esempio n. 6
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    def make_state(self, num_examples, numpy_rng):
        """ Returns a shared variable containing an actual state
           (not a mean field state) for this variable.
        """
        driver = numpy_rng.uniform(0.,1., (num_examples, self.dim))
        on_prob = sigmoid_numpy(2. * self.b.get_value())
        sample = 2. * (driver < on_prob) - 1.

        rval = sharedX(sample, name = 'v_sample_shared')

        return rval
Esempio n. 7
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 def set_biases(self, biases, recenter=False):
     self.bias.set_value(biases)
     if recenter:
         assert self.center
         self.offset.set_value(sigmoid_numpy(self.bias.get_value()))