Ejemplo n.º 1
0
def test_exponential_conditional_params():
    num_visible_units = 100
    num_hidden_units = 50
    batch_size = 25

    # set a seed for the random number generator
    be.set_seed()

    # set up some layer and model objects
    vis_layer = layers.ExponentialLayer(num_visible_units)
    hid_layer = layers.ExponentialLayer(num_hidden_units)
    rbm = model.Model([vis_layer, hid_layer])

    # randomly set the intrinsic model parameters
    # for the exponential layers, we need a > 0, b > 0, and W < 0
    a = be.rand((num_visible_units, ))
    b = be.rand((num_hidden_units, ))
    W = -be.rand((num_visible_units, num_hidden_units))

    rbm.layers[0].params.loc[:] = a
    rbm.layers[1].params.loc[:] = b
    rbm.weights[0].params.matrix[:] = W

    # generate a random batch of data
    vdata = rbm.layers[0].random((batch_size, num_visible_units))
    hdata = rbm.layers[1].random((batch_size, num_hidden_units))

    # compute conditional parameters
    hidden_rate = -be.dot(vdata, W)  # (batch_size, num_hidden_units)
    hidden_rate += be.broadcast(b, hidden_rate)

    visible_rate = -be.dot(hdata,
                           be.transpose(W))  # (batch_size, num_visible_units)
    visible_rate += be.broadcast(a, visible_rate)

    # compute the conditional parameters using the layer functions
    hidden_rate_func = rbm.layers[1]._conditional_params([vdata],
                                                         [rbm.weights[0].W()])
    visible_rate_func = rbm.layers[0]._conditional_params(
        [hdata], [rbm.weights[0].W_T()])

    assert be.allclose(hidden_rate, hidden_rate_func), \
    "hidden rate wrong in exponential-exponential rbm"

    assert be.allclose(visible_rate, visible_rate_func), \
    "visible rate wrong in exponential-exponential rbm"
Ejemplo n.º 2
0
def test_bernoulli_conditional_params():
    num_visible_units = 100
    num_hidden_units = 50
    batch_size = 25

    # set a seed for the random number generator
    be.set_seed()

    # set up some layer and model objects
    vis_layer = layers.BernoulliLayer(num_visible_units)
    hid_layer = layers.BernoulliLayer(num_hidden_units)
    rbm = model.Model([vis_layer, hid_layer])

    # randomly set the intrinsic model parameters
    a = be.randn((num_visible_units, ))
    b = be.randn((num_hidden_units, ))
    W = be.randn((num_visible_units, num_hidden_units))

    rbm.layers[0].params.loc[:] = a
    rbm.layers[1].params.loc[:] = b
    rbm.weights[0].params.matrix[:] = W

    # generate a random batch of data
    vdata = rbm.layers[0].random((batch_size, num_visible_units))
    hdata = rbm.layers[1].random((batch_size, num_hidden_units))

    # compute conditional parameters
    hidden_field = be.dot(vdata, W)  # (batch_size, num_hidden_units)
    hidden_field += b

    visible_field = be.dot(hdata,
                           be.transpose(W))  # (batch_size, num_visible_units)
    visible_field += a

    # compute conditional parameters with layer funcitons
    hidden_field_layer = rbm.layers[1]._conditional_params(
        [vdata], [rbm.weights[0].W()])
    visible_field_layer = rbm.layers[0]._conditional_params(
        [hdata], [rbm.weights[0].W_T()])

    assert be.allclose(hidden_field, hidden_field_layer), \
    "hidden field wrong in bernoulli-bernoulli rbm"

    assert be.allclose(visible_field, visible_field_layer), \
    "visible field wrong in bernoulli-bernoulli rbm"
Ejemplo n.º 3
0
def test_exponential_update():
    num_visible_units = 100
    num_hidden_units = 50
    batch_size = 25

    # set a seed for the random number generator
    be.set_seed()

    # set up some layer and model objects
    vis_layer = layers.ExponentialLayer(num_visible_units)
    hid_layer = layers.ExponentialLayer(num_hidden_units)
    rbm = hidden.Model([vis_layer, hid_layer])

    # randomly set the intrinsic model parameters
    # for the exponential layers, we need a > 0, b > 0, and W < 0
    a = be.rand((num_visible_units, ))
    b = be.rand((num_hidden_units, ))
    W = -be.rand((num_visible_units, num_hidden_units))

    rbm.layers[0].int_params['loc'] = a
    rbm.layers[1].int_params['loc'] = b
    rbm.weights[0].int_params['matrix'] = W

    # generate a random batch of data
    vdata = rbm.layers[0].random((batch_size, num_visible_units))
    hdata = rbm.layers[1].random((batch_size, num_hidden_units))

    # compute extrinsic parameters
    hidden_rate = -be.dot(vdata, W)  # (batch_size, num_hidden_units)
    hidden_rate += be.broadcast(b, hidden_rate)

    visible_rate = -be.dot(hdata,
                           be.transpose(W))  # (batch_size, num_visible_units)
    visible_rate += be.broadcast(a, visible_rate)

    # update the extrinsic parameter using the layer functions
    rbm.layers[1].update(vdata, rbm.weights[0].W())
    rbm.layers[0].update(hdata, be.transpose(rbm.weights[0].W()))

    assert be.allclose(hidden_rate, rbm.layers[1].ext_params['rate']), \
    "hidden rate wrong in exponential-exponential rbm"

    assert be.allclose(visible_rate, rbm.layers[0].ext_params['rate']), \
    "visible rate wrong in exponential-exponential rbm"
Ejemplo n.º 4
0
def test_bernoulli_update():
    num_visible_units = 100
    num_hidden_units = 50
    batch_size = 25

    # set a seed for the random number generator
    be.set_seed()

    # set up some layer and model objects
    vis_layer = layers.BernoulliLayer(num_visible_units)
    hid_layer = layers.BernoulliLayer(num_hidden_units)
    rbm = hidden.Model([vis_layer, hid_layer])

    # randomly set the intrinsic model parameters
    a = be.randn((num_visible_units, ))
    b = be.randn((num_hidden_units, ))
    W = be.randn((num_visible_units, num_hidden_units))

    rbm.layers[0].int_params.loc[:] = a
    rbm.layers[1].int_params.loc[:] = b
    rbm.weights[0].int_params.matrix[:] = W

    # generate a random batch of data
    vdata = rbm.layers[0].random((batch_size, num_visible_units))
    hdata = rbm.layers[1].random((batch_size, num_hidden_units))

    # compute extrinsic parameters
    hidden_field = be.dot(vdata, W)  # (batch_size, num_hidden_units)
    hidden_field += be.broadcast(b, hidden_field)

    visible_field = be.dot(hdata,
                           be.transpose(W))  # (batch_size, num_visible_units)
    visible_field += be.broadcast(a, visible_field)

    # update the extrinsic parameter using the layer functions
    rbm.layers[0].update([hdata], [rbm.weights[0].W_T()])
    rbm.layers[1].update([vdata], [rbm.weights[0].W()])

    assert be.allclose(hidden_field, rbm.layers[1].ext_params.field), \
    "hidden field wrong in bernoulli-bernoulli rbm"

    assert be.allclose(visible_field, rbm.layers[0].ext_params.field), \
    "visible field wrong in bernoulli-bernoulli rbm"
Ejemplo n.º 5
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def compute_weights(rbm, n_weights=25, l=0, random=True):
    # can't sample more than what we've got
    n_weights = min(n_weights, rbm.connections[l].shape[1])
    # floor to the nearest square below
    grid_size = int(sqrt(n_weights))
    n_weights = grid_size**2
    if random:
        idx = np.random.choice(range(rbm.connections[l].shape[1]),
                              n_weights, replace=False)
    else:
        idx = np.arange(n_weights)

    wprod = rbm.connections[0].weights.W()
    for i in range(1,l+1):
        wprod = be.dot(wprod, rbm.connections[i].weights.W())
    grid = np.array([be.to_numpy_array(wprod[:, i])
                        for i in idx])
    return grid.reshape(grid_size, grid_size, -1)
Ejemplo n.º 6
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def pdist(x: be.Tensor, y: be.Tensor) -> be.Tensor:
    """
    Compute the pairwise distance matrix between the rows of x and y.

    Args:
        x (tensor (num_samples_1, num_units))
        y (tensor (num_samples_2, num_units))

    Returns:
        tensor (num_samples_1, num_samples_2)

    """
    inner = be.dot(x, be.transpose(y))
    x_mag = be.norm(x, axis=1)**2
    y_mag = be.norm(y, axis=1)**2
    squared = be.add(be.unsqueeze(y_mag, axis=0),
                     be.add(be.unsqueeze(x_mag, axis=1), -2 * inner))
    return be.sqrt(be.clip(squared, a_min=0))
Ejemplo n.º 7
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def test_gaussian_update():
    num_visible_units = 100
    num_hidden_units = 50
    batch_size = 25

    # set a seed for the random number generator
    be.set_seed()

    # set up some layer and model objects
    vis_layer = layers.GaussianLayer(num_visible_units)
    hid_layer = layers.GaussianLayer(num_hidden_units)
    rbm = hidden.Model([vis_layer, hid_layer])

    # randomly set the intrinsic model parameters
    a = be.randn((num_visible_units, ))
    b = be.randn((num_hidden_units, ))
    log_var_a = 0.1 * be.randn((num_visible_units, ))
    log_var_b = 0.1 * be.randn((num_hidden_units, ))
    W = be.randn((num_visible_units, num_hidden_units))

    rbm.layers[0].int_params.loc[:] = a
    rbm.layers[1].int_params.loc[:] = b
    rbm.layers[0].int_params.log_var[:] = log_var_a
    rbm.layers[1].int_params.log_var[:] = log_var_b
    rbm.weights[0].int_params.matrix[:] = W

    # generate a random batch of data
    vdata = rbm.layers[0].random((batch_size, num_visible_units))
    hdata = rbm.layers[1].random((batch_size, num_hidden_units))

    # compute the variance
    visible_var = be.exp(log_var_a)
    hidden_var = be.exp(log_var_b)

    # rescale the data
    vdata_scaled = vdata / be.broadcast(visible_var, vdata)
    hdata_scaled = hdata / be.broadcast(hidden_var, hdata)

    # test rescale
    assert be.allclose(vdata_scaled, rbm.layers[0].rescale(vdata)),\
    "visible rescale wrong in gaussian-gaussian rbm"

    assert be.allclose(hdata_scaled, rbm.layers[1].rescale(hdata)),\
    "hidden rescale wrong in gaussian-gaussian rbm"

    # compute the mean
    hidden_mean = be.dot(vdata_scaled, W)  # (batch_size, num_hidden_units)
    hidden_mean += be.broadcast(b, hidden_mean)

    visible_mean = be.dot(hdata_scaled,
                          be.transpose(W))  # (batch_size, num_hidden_units)
    visible_mean += be.broadcast(a, visible_mean)

    # update the extrinsic parameters using the layer functions
    rbm.layers[0].update([hdata_scaled], [rbm.weights[0].W_T()])
    rbm.layers[1].update([vdata_scaled], [rbm.weights[0].W()])

    assert be.allclose(visible_var, rbm.layers[0].ext_params.variance),\
    "visible variance wrong in gaussian-gaussian rbm"

    assert be.allclose(hidden_var, rbm.layers[1].ext_params.variance),\
    "hidden variance wrong in gaussian-gaussian rbm"

    assert be.allclose(visible_mean, rbm.layers[0].ext_params.mean),\
    "visible mean wrong in gaussian-gaussian rbm"

    assert be.allclose(hidden_mean, rbm.layers[1].ext_params.mean),\
    "hidden mean wrong in gaussian-gaussian rbm"
Ejemplo n.º 8
0
def test_gaussian_conditional_params():
    num_visible_units = 100
    num_hidden_units = 50
    batch_size = 25

    # set a seed for the random number generator
    be.set_seed()

    # set up some layer and model objects
    vis_layer = layers.GaussianLayer(num_visible_units)
    hid_layer = layers.GaussianLayer(num_hidden_units)
    rbm = BoltzmannMachine([vis_layer, hid_layer])

    # randomly set the intrinsic model parameters
    a = be.randn((num_visible_units,))
    b = be.randn((num_hidden_units,))
    log_var_a = 0.1 * be.randn((num_visible_units,))
    log_var_b = 0.1 * be.randn((num_hidden_units,))
    W = be.randn((num_visible_units, num_hidden_units))

    rbm.layers[0].params.loc[:] = a
    rbm.layers[1].params.loc[:] = b
    rbm.layers[0].params.log_var[:] = log_var_a
    rbm.layers[1].params.log_var[:] = log_var_b
    rbm.connections[0].weights.params.matrix[:] = W

    # generate a random batch of data
    vdata = rbm.layers[0].random((batch_size, num_visible_units))
    hdata = rbm.layers[1].random((batch_size, num_hidden_units))

    # compute the variance
    visible_var = be.exp(log_var_a)
    hidden_var = be.exp(log_var_b)

    # rescale the data
    vdata_scaled = vdata / visible_var
    hdata_scaled = hdata / hidden_var

    # test rescale
    assert be.allclose(vdata_scaled, rbm.layers[0].rescale(vdata)),\
    "visible rescale wrong in gaussian-gaussian rbm"

    assert be.allclose(hdata_scaled, rbm.layers[1].rescale(hdata)),\
    "hidden rescale wrong in gaussian-gaussian rbm"

    # compute the mean
    hidden_mean = be.dot(vdata_scaled, W) # (batch_size, num_hidden_units)
    hidden_mean += b

    visible_mean = be.dot(hdata_scaled, be.transpose(W)) # (batch_size, num_hidden_units)
    visible_mean += a

    # update the conditional parameters using the layer functions
    vis_mean_func, vis_var_func = rbm.layers[0].conditional_params(
        [hdata_scaled], [rbm.connections[0].W(trans=True)])
    hid_mean_func, hid_var_func = rbm.layers[1].conditional_params(
        [vdata_scaled], [rbm.connections[0].W()])

    assert be.allclose(visible_var, vis_var_func),\
    "visible variance wrong in gaussian-gaussian rbm"

    assert be.allclose(hidden_var, hid_var_func),\
    "hidden variance wrong in gaussian-gaussian rbm"

    assert be.allclose(visible_mean, vis_mean_func),\
    "visible mean wrong in gaussian-gaussian rbm"

    assert be.allclose(hidden_mean, hid_mean_func),\
    "hidden mean wrong in gaussian-gaussian rbm"