Beispiel #1
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    def whitening(self) -> NumericArray:
        gpu = self.gpu
        num_pack = select_num_pack(gpu)
        precision = \
            ensure_consistent_numeric_arrays((self.inv_cov, ), gpu)[0]

        return num_pack.linalg.cholesky(precision)
Beispiel #2
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    def whitened_points(self) -> NumericArray:
        gpu = self.gpu
        num_pack = select_num_pack(gpu)
        points = \
            ensure_consistent_numeric_arrays((self.dataset.T, ), gpu)[0]

        return num_pack.dot(points, self.whitening)
Beispiel #3
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    def __init__(self,
                 dataset: NumericArray,
                 bw_method: tp.Optional[tp.Union[CovarianceFactorFunctionType,
                                                 str, tp.Callable,
                                                 numbers.Number]] = None,
                 weights: tp.Optional[NumericArray] = None,
                 gpu: bool = False):

        self._num_pack = select_num_pack(gpu)
        self._gpu = gpu
        self.dataset = atleast_2d(asarray(dataset))
        if not self.dataset.size > 1:
            raise ValueError("`dataset` input should have multiple elements.")

        self.d, self.n = self.dataset.shape

        if weights is not None:
            self._weights = atleast_1d(weights).astype(float)
            self._weights /= np.sum(self._weights)
            if self.weights.ndim != 1:
                raise ValueError("`weights` input should be one-dimensional.")
            if len(self._weights) != self.n:
                raise ValueError("`weights` input should be of length n")
            self._neff = 1.0 / np.sum(self._weights**2)
        else:
            self._weights = ones(self.n) / self.n

        self._covariance_factor = self._get_covariance_factor_function_from_bandwidth_type(
            bw_method)
        self._compute_covariance()
Beispiel #4
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def generate_data(
        n: int,
        gpu: bool) -> tp.Tuple[numpy.ndarray, numpy.ndarray, numpy.ndarray]:
    num_pack = select_num_pack(gpu)
    a = rand_with_dtype([n], dtype=numpy.float32, num_pack=num_pack)
    b = rand_with_dtype([n], dtype=numpy.float32, num_pack=num_pack)
    c = rand_with_dtype([n], dtype=numpy.float32, num_pack=num_pack)
    return a, b, c
Beispiel #5
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def estimate_pi(n: int, gpu: bool = True) -> float:
    np = select_num_pack(gpu)

    x = np.random.rand(n)
    y = np.random.rand(n)

    in_quarter_circle = (x * x + y * y) <= 1.0
    return 4.0 * float(np.mean(in_quarter_circle))
Beispiel #6
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def gaussian_kernel_estimate_vectorized_whitened(whitening: NumericArray,
                                                 whitened_points: NumericArray,
                                                 values: NumericArray,
                                                 xi: NumericArray, norm: float,
                                                 dtype: np.generic,
                                                 gpu: bool) -> NumericArray:
    # print(f'whitened_points.shape = {whitened_points.shape}')
    # print(f'values.shape = {xi.shape}')
    # print(f'xi.shape = {xi.shape}')

    n, m, d = \
        _verify_and_get_shape_of_datapoints_datavalues_and_evaluation_points(points=whitened_points,
                                                                             values=values,
                                                                             xi=xi)
    whitened_points, values, xi, whitening = \
        ensure_consistent_numeric_arrays((whitened_points, values, xi, whitening), gpu)

    num_pack = select_num_pack(gpu)

    whitened_points = whitened_points.astype(dtype, copy=False)
    whitened_xi = num_pack.dot(xi, whitening).astype(dtype, copy=False)
    values = values.astype(dtype, copy=False)

    # Create the result array and evaluate the weighted sum
    whitened_points = whitened_points.reshape((n, 1, d))
    whitened_xi = whitened_xi.reshape((1, m, d))
    residual = whitened_points - whitened_xi
    arg = residual * residual
    del residual
    if d > 1:
        assert arg.shape == (n, m, d)
        arg = num_pack.sum(arg, axis=2)
    else:
        arg = arg.reshape((n, m))
    # print(arg.shape)
    if not gpu:
        assert arg.shape == (n, m)
    arg = num_pack.exp(-0.5 * arg) * norm
    if not gpu:
        assert arg.shape == (n, m)

    # estimate = num_pack.dot(arg.T, values)
    estimate = (values * arg).sum(axis=0)
    if estimate.ndim > 1:
        estimate = estimate.squeeze()

    if gpu:
        cd.sync()

    return estimate
def estimate_pi(n: int, batches: int = 1, gpu: bool = True) -> float:
    np = select_num_pack(gpu)

    n_per_batch = math.ceil(n / batches)
    pi = 0.0
    for _ in range(batches):
        x = rand_with_dtype([n_per_batch], dtype=numpy.float32, num_pack=np)
        y = rand_with_dtype([n_per_batch], dtype=numpy.float32, num_pack=np)

        in_quarter_circle = (x * x + y * y) <= 1.0
        del x, y
        pi += 4.0 * float(np.mean(in_quarter_circle))
        del in_quarter_circle

    return pi / batches
def _compute_result_internal(R: int,
                             dimensions: tp.Tuple[int, ...],
                             arguments: tp.List[NumericArrayOrScalar],
                             functions_cpu: tp.Tuple[tp.Callable, ...],
                             functions_gpu: tp.Tuple[tp.Callable, ...],
                             pre_attach: bool,
                             gpu: bool,
                             dtype: np.generic) \
        -> NumericArray:
    """
    This function evaluates a sequence of functions with given positional
    arguments. Each argument is either a scalar or R-dimensional. The result
    Args:
        R: the number of replications (this is the length each of the input
           vectors if they are not scalars)

        dimensions:
            The shape of the output (excluding the R replications which are
            either attached to the beginning (if pre_attach is True) or to the
            end.

        arguments:
            a list of arguments to be passed to the functions to be evaluated

        functions_cpu: The sequence of functions to be evaluated on the CPU.
        functions_gpu: The sequence of functions to be evaluated on the GPU.
        pre_attach:
            whether to put the replications in the first or the last axis
        gpu: whether to evaluate on the cpu or the gpu
        dtype: the dtype of the output array

    Returns:

    """
    num_pack = select_num_pack(gpu)
    if gpu:
        functions = functions_gpu
    else:
        functions = functions_cpu

    n = (np.prod(dimensions)).item()

    if pre_attach:
        dimension_index = tuple([R] + list(dimensions))
    else:
        dimension_index = tuple(list(dimensions) + [R])

    result = num_pack.zeros(dimension_index, dtype=dtype)

    for i in range(n):
        index = tuple(np.unravel_index(i, dimensions, order='F'))

        function = functions[i]

        if pre_attach:
            location_index = tuple([slice(None)] + list(index))
        else:
            location_index = tuple(list(index) + [slice(None)])

        evaluated_function = function(*arguments)
        result[location_index] = evaluated_function

    return result
Beispiel #9
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    def normalization_constant(self) -> float:
        gpu = self.gpu
        num_pack = select_num_pack(gpu)

        return (2 * np.pi)**(-self.d / 2) * num_pack.prod(
            num_pack.diag(self.whitening))
Beispiel #10
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def gaussian_kernel_estimate_vectorized(points: NumericArray,
                                        values: NumericArray,
                                        xi: NumericArray,
                                        precision: NumericArray,
                                        dtype: np.generic,
                                        gpu: bool = False) \
        -> NumericArray:
    """
    def gaussian_kernel_estimate(points, real[:, :] values, xi, precision)
    Evaluate a multivariate Gaussian kernel estimate.
    Parameters
    ----------
    points : array_like with shape (n, d)
        Data points to estimate from in d dimenions.
    values : real[:, :] with shape (n, p)
        Multivariate values associated with the data points.
    xi : array_like with shape (m, d)
        Coordinates to evaluate the estimate at in d dimensions.
    precision : array_like with shape (d, d)
        Precision matrix for the Gaussian kernel.
    dtype : the result dtype
    gpu : whether to compute the gaussian kernel estimate on the gpu

    Returns
    -------
    estimate : double[:, :] with shape (m, p)
        Multivariate Gaussian kernel estimate evaluated at the input coordinates.
    """
    num_pack = select_num_pack(gpu)
    n, m, d = \
        _verify_and_get_shape_of_datapoints_datavalues_and_evaluation_points(points=points,
                                                                             values=values,
                                                                             xi=xi)

    # n = points.shape[0]
    #
    # if points.ndim > 1:
    #     d = points.shape[1]
    # else:
    #     d = 1
    # m = xi.shape[0]
    #
    # if values.ndim > 1:
    #     p = values.shape[1]
    # else:
    #     p = 1
    #
    # if p != 1:
    #     raise ValueError('p != 1 is not supported')
    #
    # if xi.shape[1] != d:
    #     raise ValueError("points and xi must have same trailing dim")
    # if precision.shape[0] != d or precision.shape[1] != d:
    #     raise ValueError("precision matrix must match data dims")

    points, values, xi, precision = \
        ensure_consistent_numeric_arrays((points, values, xi, precision), gpu)

    # Rescale the data
    whitening = num_pack.linalg.cholesky(precision).astype(dtype, copy=False)
    points = num_pack.dot(points, whitening).astype(dtype, copy=False)
    # xi = num_pack.dot(xi, whitening).astype(dtype, copy=False)
    values = values.astype(dtype, copy=False)

    # Evaluate the normalisation
    norm = (2 * np.pi)**(-d / 2) * num_pack.prod(num_pack.diag(whitening))

    # # Create the result array and evaluate the weighted sum
    # points = points.reshape((n, 1, d))
    # xi = xi.reshape((1, m, d))
    # residual = points - xi
    # arg = residual * residual
    # del residual
    # if d > 1:
    #     assert arg.shape == (n, m, d)
    #     arg = num_pack.sum(arg, axis=2)
    # else:
    #     arg = arg.reshape((n, m))
    # assert arg.shape == (n, m)
    # arg = num_pack.exp(- 0.5 * arg) * norm
    # assert arg.shape == (n, m)
    #
    # estimate = num_pack.dot(arg.T, values)
    #
    # if gpu:
    #     cd.sync()
    #
    # return estimate.squeeze()

    return gaussian_kernel_estimate_vectorized_whitened(whitening=whitening,
                                                        whitened_points=points,
                                                        xi=xi,
                                                        values=values,
                                                        norm=norm,
                                                        dtype=dtype,
                                                        gpu=gpu)
Beispiel #11
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def process_data(a: NumericArray, b: NumericArray, c: NumericArray, gpu: bool):
    np = select_num_pack(gpu)

    return (np.sin(a) + np.cos(b)) * np.arctan(c)