Exemplo n.º 1
0
    def __theano_build__(self):
        W1 = self.W1
        W2 = self.W2
        b1 = self.b1
        b2 = self.b2
        x = dvector(name="x")
        y = dvector(name="y")
        def forward(x):
            h = T.tanh(x.dot(W1) + b1)
            o = T.nnet.softmax(h.dot(W2) + b2)
            return o
        
        o = forward(x)
        prediction = T.argmax(o, axis=1)
        o_error = ((y-o)**2).sum()
        
        dW1 = T.grad(o_error, W1)
        dW2 = T.grad(o_error, W2)
        db1 = T.grad(o_error, b1)
        db2 = T.grad(o_error, b2)
        
        self.forward_propagation = theano.function([x], o)
        self.predict = theano.function([x], prediction)
        self.cerror = theano.function([x, y], o_error)
 
        learning_rate = T.scalar("learning_rate")
        self.sgd_step = theano.function([x,y,learning_rate], [], 
                                        updates=[(self.W1, self.W1-learning_rate*dW1),
                                                 (self.W2, self.W2-learning_rate*dW2),
                                                 (self.b1, self.b1-learning_rate*db1),
                                                 (self.b2, self.b2-learning_rate*db2)])
Exemplo n.º 2
0
 def make_node(self, M):
     M = basic.as_tensor_variable(M)
     if M.ndim != 0:
         raise TypeError(
             f"{self.__class__.__name__} only works on scalar input")
     elif M.dtype not in theano.tensor.integer_dtypes:
         # dtype is a theano attribute here
         raise TypeError(
             f"{self.__class__.__name__} only works on integer input")
     return Apply(self, [M], [basic.dvector()])
Exemplo n.º 3
0
    def test_2arg(self):
        x = dmatrix("x")
        x.tag.test_value = np.zeros((2, 2))
        y = dvector("y")
        y.tag.test_value = [0, 0, 0, 0]

        @as_op([dmatrix, dvector], dvector)
        def cumprod_plus(x, y):
            return np.cumprod(x) + y

        fn = function([x, y], cumprod_plus(x, y))
        r = fn([[1.5, 5], [2, 2]], [1, 100, 2, 200])
        r0 = np.array([2.5, 107.5, 17.0, 230.0])

        assert np.allclose(r, r0), (r, r0)
Exemplo n.º 4
0
    def make_node(self, x, weights):
        warnings.warn((
            "Tile op is deprecated, use tile function instead."),
            stacklevel=3)

        x = basic.as_tensor_variable(x)

        if x.dtype not in BinCountOp.compatible_type:
            raise TypeError("Inputs dtype must be an integer.")

        # Some dtypes are not supported by numpy's implementation of bincount.
        # Until another one is available, we should fail at graph construction
        # time, not wait for execution.
        int_bitwidth = theano.gof.python_int_bitwidth()
        if int_bitwidth == 64:
            numpy_unsupported_dtypes = ('uint64',)
        if int_bitwidth == 32:
            numpy_unsupported_dtypes = ('uint32', 'int64', 'uint64')
        intp_bitwidth = theano.gof.local_bitwidth()
        if intp_bitwidth == 32:
            out_type = basic.ivector()
        elif intp_bitwidth == 64:
            out_type = basic.lvector()

        if x.dtype in numpy_unsupported_dtypes:
            raise TypeError(
                ("Input dtypes %s are not supported by numpy.bincount, "
                 % numpy_unsupported_dtypes), x.dtype)

        if x.ndim != 1:
            raise TypeError("Inputs must be of dimension 1.")

        if weights is None:
            weights = theano.gof.Constant(theano.gof.Generic(), None)
        else:
            weights = basic.as_tensor_variable(weights)
            out_type = basic.dvector()
            if weights.ndim != 1:
                raise TypeError("Weights cannot have a number of"
                                "dimension different of 1.")

        return theano.Apply(self, [x, weights], [out_type])
Exemplo n.º 5
0
    def test_infer_shape(self):
        x = dmatrix("x")
        x.tag.test_value = np.zeros((2, 2))
        y = dvector("y")
        y.tag.test_value = [0, 0, 0, 0]

        def infer_shape(fgraph, node, shapes):
            x, y = shapes
            return [y]

        @as_op([dmatrix, dvector], dvector, infer_shape)
        def cumprod_plus(x, y):
            return np.cumprod(x) + y

        self._compile_and_check(
            [x, y],
            [cumprod_plus(x, y)],
            [[[1.5, 5], [2, 2]], [1, 100, 2, 200]],
            cumprod_plus.__class__,
            warn=False,
        )