Python tensor.cos函数代码示例

  def get_output_for(self, inputs, **kwargs):
    # see eq. (1) and sec 3.1 in [1]
    input, para = inputs
    num_batch, channels, height, width = input.shape
    _w = T.cast(width, dtype = self.dtype)
    _h = T.cast(height, dtype = self.dtype)
    mat = T.zeros((num_batch, 3, 3), dtype = self.dtype)
    mat = T.set_subtensor(mat[:, 0, 0], const(1.0))
    mat = T.set_subtensor(mat[:, 1, 1], const(1.0))
    mat = T.set_subtensor(mat[:, 2, 2], const(1.0))

    if self.method == 'perspective':
      mat = T.set_subtensor(mat[:, 2, 0], (para[:, 0] / 1e4 - 1e-3) * _w)
      mat = T.set_subtensor(mat[:, 2, 1], (para[:, 1] / 1e4 - 1e-3) * _h)
    elif self.method == 'angle':
      angle = T.cast(T.argmax(para, axis = 1), dtype = self.dtype) * np.pi / 90 - np.pi / 3.0
      # ss = np.sqrt(2.0)
      mat = T.set_subtensor(mat[:, :, :], T.stacklists([
        [T.cos(angle), T.sin(angle), -(T.cos(angle) * _w + T.sin(angle) * _h - _w) / (2.0 * _w)],
        [-T.sin(angle), T.cos(angle), -(-T.sin(angle) * _w + T.cos(angle) * _h - _h) / (2.0 * _h)],
        [constv(0, num_batch, self.dtype), constv(0, num_batch, self.dtype), constv(1, num_batch, self.dtype)]]).dimshuffle(2, 0, 1))
      # return [mat, _w, _h]
    elif self.method == 'all':
      mat = T.reshape(para, [-1, 3, 3])
      mat = T.set_subtensor(mat[:, 0, 2], mat[:, 0, 2] / T.cast(width, dtype))
      mat = T.set_subtensor(mat[:, 1, 2], mat[:, 1, 2] / T.cast(height, dtype))
      mat = T.set_subtensor(mat[:, 2, 0], mat[:, 2, 0] * T.cast(width, dtype))
      mat = T.set_subtensor(mat[:, 2, 1], mat[:, 2, 1] * T.cast(height, dtype))
    else:
      raise Exception('method not understood.')
    return transform_affine(mat, input, self.method, scale_factor = self.scale_factor)

def arc_distance_theano_alloc_prepare(dtype='float64'):
    """
    Calculates the pairwise arc distance between all points in vector a and b.
    """
    a = tensor.matrix(dtype=str(dtype))
    b = tensor.matrix(dtype=str(dtype))
    # Theano don't implement all case of tile, so we do the equivalent with alloc.
    #theta_1 = tensor.tile(a[:, 0], (b.shape[0], 1)).T
    theta_1 = tensor.alloc(a[:, 0], b.shape[0], b.shape[0]).T
    phi_1 = tensor.alloc(a[:, 1], b.shape[0], b.shape[0]).T

    theta_2 = tensor.alloc(b[:, 0], a.shape[0], a.shape[0])
    phi_2 = tensor.alloc(b[:, 1], a.shape[0], a.shape[0])

    temp = (tensor.sin((theta_2 - theta_1) / 2)**2
            +
            tensor.cos(theta_1) * tensor.cos(theta_2)
            * tensor.sin((phi_2 - phi_1) / 2)**2)
    distance_matrix = 2 * (tensor.arctan2(tensor.sqrt(temp),
                                          tensor.sqrt(1 - temp)))
    name = "arc_distance_theano_alloc"
    rval = theano.function([a, b],
                           distance_matrix,
                           name=name)
    rval.__name__ = name

    return rval

def arc_distance_theano_broadcast_prepare(dtype='float64'):
    """
    Calculates the pairwise arc distance between all points in vector a and b.
    """
    a = tensor.matrix(dtype=str(dtype))
    b = tensor.matrix(dtype=str(dtype))

    theta_1 = a[:, 0][None, :]
    theta_2 = b[:, 0][None, :]
    phi_1 = a[:, 1][:, None]
    phi_2 = b[:, 1][None, :]

    temp = (tensor.sin((theta_2 - theta_1) / 2)**2
            +
            tensor.cos(theta_1) * tensor.cos(theta_2)
            * tensor.sin((phi_2 - phi_1) / 2)**2)
    distance_matrix = 2 * (tensor.arctan2(tensor.sqrt(temp),
                                          tensor.sqrt(1 - temp)))
    name = "arc_distance_theano_broadcast"
    rval = theano.function([a, b],
                           distance_matrix,
                           name=name)
    rval.__name__ = name

    return rval

 def _forward_scat(self):
     alpha_border = 1.2  # Greg & Carder
     cos_theta = T.switch(T.gt(self.symbols['alpha'], alpha_border), 0.65, -0.1417 * self.symbols['alpha'] + 0.82)
     B3 = T.log(1 - cos_theta)
     B2 = B3 * (0.0783 + B3 * (-0.3824 - 0.5874 * B3))
     B1 = B3 * (1.459 + B3 * (0.1595 + 0.4129 * B3))
     return 1 - 0.5 * T.exp((B1 + B2 * T.cos(self.zenith_rad)) * T.cos(self.zenith_rad))

    def get_celerite_matrices(self, x, diag):
        x = tt.as_tensor_variable(x)
        diag = tt.as_tensor_variable(diag)
        ar, cr, ac, bc, cc, dc = self.coefficients
        a = diag + tt.sum(ar) + tt.sum(ac)
        U = tt.concatenate((
            ar[None, :] + tt.zeros_like(x)[:, None],
            ac[None, :] * tt.cos(dc[None, :] * x[:, None])
            + bc[None, :] * tt.sin(dc[None, :] * x[:, None]),
            ac[None, :] * tt.sin(dc[None, :] * x[:, None])
            - bc[None, :] * tt.cos(dc[None, :] * x[:, None]),
        ), axis=1)

        V = tt.concatenate((
            tt.zeros_like(ar)[None, :] + tt.ones_like(x)[:, None],
            tt.cos(dc[None, :] * x[:, None]),
            tt.sin(dc[None, :] * x[:, None]),
        ), axis=1)

        dx = x[1:] - x[:-1]
        P = tt.concatenate((
            tt.exp(-cr[None, :] * dx[:, None]),
            tt.exp(-cc[None, :] * dx[:, None]),
            tt.exp(-cc[None, :] * dx[:, None]),
        ), axis=1)

        return a, U, V, P

def get_uhs_operator(uhs, depth, n_hidden, rhos):
    """

    :param uhs:
    :param depth:
    :param n_hidden:
    :param rhos: can be shared variable or constant of shape (depth, )!!
    :return:
    """
    # Will use a Fourier matrix (will be O(n^2)...)
    # Doesn't seem to slow things down much though!
    exp_phases = [T.cos(uhs), T.sin(uhs)]
    neg_exp_phases = [T.cos(uhs[:, ::-1]), -T.sin(uhs[:, ::-1])]
    ones_ = [T.ones((depth, 1), dtype=theano.config.floatX), T.zeros((depth, 1), dtype=theano.config.floatX)]

    rhos_reshaped = T.reshape(rhos, (depth, 1), ndim=2)
    rhos_reshaped = T.addbroadcast(rhos_reshaped, 1)

    eigvals_re = rhos_reshaped * T.concatenate((ones_[0], exp_phases[0], -ones_[0], neg_exp_phases[0]), axis=1)
    eigvals_im = rhos_reshaped * T.concatenate((ones_[1], exp_phases[1], -ones_[1], neg_exp_phases[1]), axis=1)
    phase_array = -2 * np.pi * np.outer(np.arange(n_hidden), np.arange(n_hidden)) / n_hidden
    f_array_re_val = np.cos(phase_array) / n_hidden
    f_array_im_val = np.sin(phase_array) / n_hidden
    f_array_re = theano.shared(f_array_re_val.astype(theano.config.floatX), name="f_arr_re")
    f_array_im = theano.shared(f_array_im_val.astype(theano.config.floatX), name="f_arr_im")

    a_k = T.dot(eigvals_re, f_array_re) + T.dot(eigvals_im, f_array_im)
    uhs_op = rep_vec(a_k, n_hidden, n_hidden)  # shape (depth, 2 * n_hidden - 1)

    return uhs_op

def poseDiff2D(startingPose, endingPose):
    x1, y1, theta1 = endingPose[0], endingPose[1], endingPose[2]
    x2, y2, theta2 = startingPose[0], startingPose[1], startingPose[2]
    dx = (x1 - x2)*T.cos(theta2) + (y1 - y2)*T.sin(theta2)
    dy = -(x1 - x2)*T.sin(theta2) + (y1 - y2)*T.cos(theta2)
    dtheta = normalizeAngle(theta1 - theta2)
    return dx, dy, dtheta

    def grad(self, inputs, gradients):
        M, e = inputs
        E, f = self(M, e)

        bM = tt.zeros_like(M)
        be = tt.zeros_like(M)
        ecosE = e * tt.cos(E)

        if not isinstance(gradients[0].type, theano.gradient.DisconnectedType):
            # Backpropagate E_bar
            bM = gradients[0] / (1 - ecosE)
            be = tt.sin(E) * bM

        if not isinstance(gradients[1].type, theano.gradient.DisconnectedType):
            # Backpropagate f_bar
            sinf2 = tt.sin(0.5*f)
            cosf2 = tt.cos(0.5*f)
            tanf2 = sinf2 / cosf2
            e2 = e**2
            ome2 = 1 - e2
            ome = 1 - e
            ope = 1 + e
            cosf22 = cosf2**2
            twoecosf22 = 2 * e * cosf22
            factor = tt.sqrt(ope/ome)
            inner = (twoecosf22+ome) * tt.as_tensor_variable(gradients[1])

            bM += factor*(ome*tanf2**2+ope)*inner*cosf22/(ope*ome2)
            be += -2*cosf22*tanf2/ome2**2*inner*(ecosE-2+e2)

        return [bM, be]

 def _getrz(self,d):
     r=theano.shared(np.zeros((3,3),dtype='float32'))
     r=T.set_subtensor(r[2,2],1.0)
     r=T.set_subtensor(r[0,0],T.cos(d))
     r=T.set_subtensor(r[0,1],-T.sin(d))
     r=T.set_subtensor(r[1,0],T.sin(d))
     r=T.set_subtensor(r[1,1],T.cos(d))        
     return r

 def alpha_perfect(self, w, u):
     alpha = sharedX(1.5)
     beta = sharedX(0.5)
     S_var = self.S(alpha,beta)
     B_var = self.B(alpha,beta)
     first = T.sin(alpha*(u+B_var)/(T.cos(u)**(1/alpha)))
     second = T.cos(u-alpha*(u+B_var))/w
     return S_var*first*(second**((1-alpha)/alpha))

 def generator(self, u):
     if u.ndim == 1:
         u = u[None, :]
     z, n = u[:, :self.z_dim], u[:, self.z_dim:self.z_dim + self.x_dim]
     loc, scale = self.x_gvn_z(z)
     alpha = 2 * scale / (1 + scale**2)
     phi = tt.arccos((tt.cos(2 * np.pi * n) + alpha) /
                     (1 + alpha * tt.cos(2 * np.pi * n))) + loc
     return tt.switch(n < 0.5, phi, 2 * np.pi - phi)

def xyz(R1, theta, R2, phi):
    theta_ = T.scalar('theta')
    phi_ = T.scalar('phi')

    x = R1 * T.cos(theta_) * R2 * T.cos(phi_)
    y = R2 * T.sin(theta_) * R2 * T.cos(phi_)
    z = R2 * T.sin(phi_)
    func = function([theta_, phi_], [x, y, z], allow_input_downcast=True)
    vals = func(theta, phi)
    return vals[0].flatten(), vals[1].flatten(), vals[2].flatten()

def xyz2(theta, a, b, m, n1, n2, n3, rho, a2, b2, m2, n4, n5, n6):
    theta_ = T.scalar('theta')
    rho_ = T.scalar('rho')
    R1 = R(theta, a, b, m, n1, n2, n3)
    R2 = R(rho, a2, b2, m2, n4, n5, n6)

    x = R1 * T.cos(theta_) * R2 * T.cos(rho_)
    y = R1 * T.sin(theta_) * R2 * T.cos(rho_)
    z = R2 * T.sin(rho_)
    func = function([theta_, rho_], [x, y, z], allow_input_downcast=True)
    vals = func(theta, rho)
    return vals[0].flatten(), vals[1].flatten(), vals[2].flatten()

 def get_output(self, train=False):
     rnorm = self.omega / np.sqrt(2*np.pi)*self.kappa
     val = - self.omega**2 / (8 * self.kappa**2)
     dir1 = 4 * (self._outter(self.x, tensor.cos(self.theta)) +
                 self._outter(self.y, tensor.sin(self.theta)))**2
     dir2 = (-self._outter(self.x, tensor.sin(self.theta)) +
             self._outter(self.y, tensor.cos(self.theta)))**2
     ex = 1j * (self.omega * self._outter(tensor.cos(self.theta), self.x) +
                self.omega * self._outter(tensor.sin(self.theta), self.y))
     output = rnorm * tensor.exp(val * (dir1 + dir2)) * (tensor.exp(ex)
                                                         - tensor.exp(-self.kappa**2 / 2))
     return output

 def __init__(self, target, initial_phi, profile_s=None, A0=1.0):
     self.target = target
     self.n_pixels = int(target.shape[0] / 2)   # target should be 512x512, but SLM pattern calculated should be 256x256.
     self.intensity_calc = None
     
     self.cost = None   # placeholder for cost function.
     
     if profile_s is None:
         profile_s = np.ones((self.n_pixels, self.n_pixels))
         
     assert profile_s.shape == (self.n_pixels, self.n_pixels), 'profile_s is wrong shape, should be ({n},{n})'.format(n=self.n_pixels)
     self.profile_s_r = profile_s.real.astype('float64')
     self.profile_s_i = profile_s.imag.astype('float64')
     
     assert initial_phi.shape == (self.n_pixels**2,), "initial_phi must be a vector of phases of size N^2 (not (N,N)).  Shape is " + str(initial_phi.shape)
     
     self.A0 = A0
     
     # Set zeros matrix:
     self.zero_frame = np.zeros((2*self.n_pixels, 2*self.n_pixels), dtype='float64')
     
     # Phi and its momentum for use in gradient descent with momentum:
     self.phi    = theano.shared(value=initial_phi.astype('float64'),
                                 name='phi')
     self.phi_rate = theano.shared(value=np.zeros_like(initial_phi).astype('float64'),
                                   name='phi_rate')
     
     self.S_r = theano.shared(value=self.profile_s_r,
                              name='s_r')
     self.S_i = theano.shared(value=self.profile_s_i,
                              name='s_i')
     self.zero_matrix = theano.shared(value=self.zero_frame,
                                      name='zero_matrix')
     
     # E_in: (n_pixels**2)
     phi_reshaped = self.phi.reshape((self.n_pixels, self.n_pixels))
     self.E_in_r = self.A0 * (self.S_r*T.cos(phi_reshaped) - self.S_i*T.sin(phi_reshaped))
     self.E_in_i = self.A0 * (self.S_i*T.cos(phi_reshaped) + self.S_r*T.sin(phi_reshaped))
     
     # E_in padded: (4n_pixels**2)
     idx_0, idx_1 = get_centre_range(self.n_pixels)
     self.E_in_r_pad = T.set_subtensor(self.zero_matrix[idx_0:idx_1,idx_0:idx_1], self.E_in_r)
     self.E_in_i_pad = T.set_subtensor(self.zero_matrix[idx_0:idx_1,idx_0:idx_1], self.E_in_i)
     
     # E_out:
     self.E_out_r, self.E_out_i = fft(self.E_in_r_pad, self.E_in_i_pad)        
     
     # finally, the output intensity:
     self.E_out_2 = T.add(T.pow(self.E_out_r, 2), T.pow(self.E_out_i, 2))