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* add fftshift and ifftshift fft helpers * address comments * axes have to be iterable * fix fp error in roll + add test --------- Co-authored-by: Aashiq Dheeraj <aashiq@aashiq-mbp-m4.local>
514 lines
18 KiB
C++
514 lines
18 KiB
C++
// Copyright © 2023-2024 Apple Inc.
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#include <nanobind/nanobind.h>
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#include <nanobind/stl/optional.h>
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#include <nanobind/stl/variant.h>
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#include <nanobind/stl/vector.h>
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#include <numeric>
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#include "mlx/fft.h"
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#include "mlx/ops.h"
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namespace mx = mlx::core;
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namespace nb = nanobind;
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using namespace nb::literals;
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void init_fft(nb::module_& parent_module) {
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auto m = parent_module.def_submodule(
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"fft", "mlx.core.fft: Fast Fourier Transforms.");
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m.def(
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"fft",
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[](const mx::array& a,
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const std::optional<int>& n,
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int axis,
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mx::StreamOrDevice s) {
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if (n.has_value()) {
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return mx::fft::fft(a, n.value(), axis, s);
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} else {
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return mx::fft::fft(a, axis, s);
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}
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},
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"a"_a,
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"n"_a = nb::none(),
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"axis"_a = -1,
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"stream"_a = nb::none(),
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R"pbdoc(
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One dimensional discrete Fourier Transform.
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Args:
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a (array): The input array.
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n (int, optional): Size of the transformed axis. The
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corresponding axis in the input is truncated or padded with
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zeros to match ``n``. The default value is ``a.shape[axis]``.
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axis (int, optional): Axis along which to perform the FFT. The
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default is ``-1``.
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Returns:
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array: The DFT of the input along the given axis.
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)pbdoc");
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m.def(
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"ifft",
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[](const mx::array& a,
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const std::optional<int>& n,
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int axis,
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mx::StreamOrDevice s) {
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if (n.has_value()) {
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return mx::fft::ifft(a, n.value(), axis, s);
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} else {
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return mx::fft::ifft(a, axis, s);
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}
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},
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"a"_a,
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"n"_a = nb::none(),
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"axis"_a = -1,
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"stream"_a = nb::none(),
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R"pbdoc(
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One dimensional inverse discrete Fourier Transform.
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Args:
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a (array): The input array.
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n (int, optional): Size of the transformed axis. The
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corresponding axis in the input is truncated or padded with
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zeros to match ``n``. The default value is ``a.shape[axis]``.
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axis (int, optional): Axis along which to perform the FFT. The
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default is ``-1``.
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Returns:
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array: The inverse DFT of the input along the given axis.
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)pbdoc");
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m.def(
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"fft2",
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[](const mx::array& a,
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const std::optional<mx::Shape>& n,
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const std::optional<std::vector<int>>& axes,
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mx::StreamOrDevice s) {
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if (axes.has_value() && n.has_value()) {
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return mx::fft::fftn(a, n.value(), axes.value(), s);
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} else if (axes.has_value()) {
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return mx::fft::fftn(a, axes.value(), s);
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} else if (n.has_value()) {
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throw std::invalid_argument(
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"[fft2] `axes` should not be `None` if `s` is not `None`.");
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} else {
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return mx::fft::fftn(a, s);
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}
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},
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"a"_a,
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"s"_a = nb::none(),
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"axes"_a.none() = std::vector<int>{-2, -1},
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"stream"_a = nb::none(),
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R"pbdoc(
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Two dimensional discrete Fourier Transform.
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Args:
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a (array): The input array.
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s (list(int), optional): Sizes of the transformed axes. The
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corresponding axes in the input are truncated or padded with
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zeros to match the sizes in ``s``. The default value is the
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sizes of ``a`` along ``axes``.
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axes (list(int), optional): Axes along which to perform the FFT.
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The default is ``[-2, -1]``.
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Returns:
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array: The DFT of the input along the given axes.
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)pbdoc");
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m.def(
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"ifft2",
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[](const mx::array& a,
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const std::optional<mx::Shape>& n,
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const std::optional<std::vector<int>>& axes,
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mx::StreamOrDevice s) {
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if (axes.has_value() && n.has_value()) {
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return mx::fft::ifftn(a, n.value(), axes.value(), s);
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} else if (axes.has_value()) {
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return mx::fft::ifftn(a, axes.value(), s);
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} else if (n.has_value()) {
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throw std::invalid_argument(
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"[ifft2] `axes` should not be `None` if `s` is not `None`.");
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} else {
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return mx::fft::ifftn(a, s);
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}
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},
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"a"_a,
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"s"_a = nb::none(),
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"axes"_a.none() = std::vector<int>{-2, -1},
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"stream"_a = nb::none(),
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R"pbdoc(
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Two dimensional inverse discrete Fourier Transform.
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Args:
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a (array): The input array.
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s (list(int), optional): Sizes of the transformed axes. The
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corresponding axes in the input are truncated or padded with
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zeros to match the sizes in ``s``. The default value is the
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sizes of ``a`` along ``axes``.
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axes (list(int), optional): Axes along which to perform the FFT.
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The default is ``[-2, -1]``.
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Returns:
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array: The inverse DFT of the input along the given axes.
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)pbdoc");
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m.def(
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"fftn",
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[](const mx::array& a,
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const std::optional<mx::Shape>& n,
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const std::optional<std::vector<int>>& axes,
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mx::StreamOrDevice s) {
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if (axes.has_value() && n.has_value()) {
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return mx::fft::fftn(a, n.value(), axes.value(), s);
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} else if (axes.has_value()) {
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return mx::fft::fftn(a, axes.value(), s);
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} else if (n.has_value()) {
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throw std::invalid_argument(
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"[fftn] `axes` should not be `None` if `s` is not `None`.");
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} else {
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return mx::fft::fftn(a, s);
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}
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},
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"a"_a,
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"s"_a = nb::none(),
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"axes"_a = nb::none(),
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"stream"_a = nb::none(),
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R"pbdoc(
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n-dimensional discrete Fourier Transform.
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Args:
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a (array): The input array.
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s (list(int), optional): Sizes of the transformed axes. The
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corresponding axes in the input are truncated or padded with
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zeros to match the sizes in ``s``. The default value is the
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sizes of ``a`` along ``axes``.
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axes (list(int), optional): Axes along which to perform the FFT.
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The default is ``None`` in which case the FFT is over the last
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``len(s)`` axes are or all axes if ``s`` is also ``None``.
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Returns:
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array: The DFT of the input along the given axes.
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)pbdoc");
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m.def(
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"ifftn",
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[](const mx::array& a,
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const std::optional<mx::Shape>& n,
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const std::optional<std::vector<int>>& axes,
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mx::StreamOrDevice s) {
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if (axes.has_value() && n.has_value()) {
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return mx::fft::ifftn(a, n.value(), axes.value(), s);
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} else if (axes.has_value()) {
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return mx::fft::ifftn(a, axes.value(), s);
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} else if (n.has_value()) {
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throw std::invalid_argument(
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"[ifftn] `axes` should not be `None` if `s` is not `None`.");
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} else {
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return mx::fft::ifftn(a, s);
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}
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},
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"a"_a,
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"s"_a = nb::none(),
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"axes"_a = nb::none(),
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"stream"_a = nb::none(),
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R"pbdoc(
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n-dimensional inverse discrete Fourier Transform.
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Args:
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a (array): The input array.
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s (list(int), optional): Sizes of the transformed axes. The
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corresponding axes in the input are truncated or padded with
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zeros to match the sizes in ``s``. The default value is the
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sizes of ``a`` along ``axes``.
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axes (list(int), optional): Axes along which to perform the FFT.
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The default is ``None`` in which case the FFT is over the last
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``len(s)`` axes or all axes if ``s`` is also ``None``.
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Returns:
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array: The inverse DFT of the input along the given axes.
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)pbdoc");
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m.def(
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"rfft",
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[](const mx::array& a,
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const std::optional<int>& n,
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int axis,
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mx::StreamOrDevice s) {
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if (n.has_value()) {
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return mx::fft::rfft(a, n.value(), axis, s);
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} else {
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return mx::fft::rfft(a, axis, s);
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}
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},
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"a"_a,
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"n"_a = nb::none(),
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"axis"_a = -1,
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"stream"_a = nb::none(),
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R"pbdoc(
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One dimensional discrete Fourier Transform on a real input.
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The output has the same shape as the input except along ``axis`` in
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which case it has size ``n // 2 + 1``.
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Args:
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a (array): The input array. If the array is complex it will be silently
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cast to a real type.
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n (int, optional): Size of the transformed axis. The
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corresponding axis in the input is truncated or padded with
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zeros to match ``n``. The default value is ``a.shape[axis]``.
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axis (int, optional): Axis along which to perform the FFT. The
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default is ``-1``.
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Returns:
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array: The DFT of the input along the given axis. The output
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data type will be complex.
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)pbdoc");
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m.def(
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"irfft",
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[](const mx::array& a,
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const std::optional<int>& n,
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int axis,
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mx::StreamOrDevice s) {
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if (n.has_value()) {
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return mx::fft::irfft(a, n.value(), axis, s);
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} else {
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return mx::fft::irfft(a, axis, s);
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}
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},
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"a"_a,
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"n"_a = nb::none(),
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"axis"_a = -1,
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"stream"_a = nb::none(),
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R"pbdoc(
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The inverse of :func:`rfft`.
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The output has the same shape as the input except along ``axis`` in
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which case it has size ``n``.
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Args:
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a (array): The input array.
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n (int, optional): Size of the transformed axis. The
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corresponding axis in the input is truncated or padded with
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zeros to match ``n // 2 + 1``. The default value is
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``a.shape[axis] // 2 + 1``.
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axis (int, optional): Axis along which to perform the FFT. The
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default is ``-1``.
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Returns:
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array: The real array containing the inverse of :func:`rfft`.
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)pbdoc");
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m.def(
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"rfft2",
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[](const mx::array& a,
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const std::optional<mx::Shape>& n,
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const std::optional<std::vector<int>>& axes,
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mx::StreamOrDevice s) {
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if (axes.has_value() && n.has_value()) {
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return mx::fft::rfftn(a, n.value(), axes.value(), s);
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} else if (axes.has_value()) {
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return mx::fft::rfftn(a, axes.value(), s);
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} else if (n.has_value()) {
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throw std::invalid_argument(
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"[rfft2] `axes` should not be `None` if `s` is not `None`.");
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} else {
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return mx::fft::rfftn(a, s);
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}
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},
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"a"_a,
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"s"_a = nb::none(),
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"axes"_a.none() = std::vector<int>{-2, -1},
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"stream"_a = nb::none(),
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R"pbdoc(
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Two dimensional real discrete Fourier Transform.
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The output has the same shape as the input except along the dimensions in
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``axes`` in which case it has sizes from ``s``. The last axis in ``axes`` is
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treated as the real axis and will have size ``s[-1] // 2 + 1``.
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Args:
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a (array): The input array. If the array is complex it will be silently
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cast to a real type.
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s (list(int), optional): Sizes of the transformed axes. The
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corresponding axes in the input are truncated or padded with
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zeros to match the sizes in ``s``. The default value is the
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sizes of ``a`` along ``axes``.
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axes (list(int), optional): Axes along which to perform the FFT.
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The default is ``[-2, -1]``.
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Returns:
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array: The real DFT of the input along the given axes. The output
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data type will be complex.
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)pbdoc");
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m.def(
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"irfft2",
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[](const mx::array& a,
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const std::optional<mx::Shape>& n,
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const std::optional<std::vector<int>>& axes,
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mx::StreamOrDevice s) {
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if (axes.has_value() && n.has_value()) {
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return mx::fft::irfftn(a, n.value(), axes.value(), s);
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} else if (axes.has_value()) {
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return mx::fft::irfftn(a, axes.value(), s);
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} else if (n.has_value()) {
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throw std::invalid_argument(
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"[irfft2] `axes` should not be `None` if `s` is not `None`.");
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} else {
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return mx::fft::irfftn(a, s);
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}
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},
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"a"_a,
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"s"_a = nb::none(),
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"axes"_a.none() = std::vector<int>{-2, -1},
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"stream"_a = nb::none(),
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R"pbdoc(
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The inverse of :func:`rfft2`.
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Note the input is generally complex. The dimensions of the input
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specified in ``axes`` are padded or truncated to match the sizes
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from ``s``. The last axis in ``axes`` is treated as the real axis
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and will have size ``s[-1] // 2 + 1``.
|
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Args:
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a (array): The input array.
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s (list(int), optional): Sizes of the transformed axes. The
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corresponding axes in the input are truncated or padded with
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zeros to match the sizes in ``s`` except for the last axis
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which has size ``s[-1] // 2 + 1``. The default value is the
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sizes of ``a`` along ``axes``.
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axes (list(int), optional): Axes along which to perform the FFT.
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The default is ``[-2, -1]``.
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Returns:
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array: The real array containing the inverse of :func:`rfft2`.
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)pbdoc");
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m.def(
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"rfftn",
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[](const mx::array& a,
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const std::optional<mx::Shape>& n,
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const std::optional<std::vector<int>>& axes,
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mx::StreamOrDevice s) {
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if (axes.has_value() && n.has_value()) {
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return mx::fft::rfftn(a, n.value(), axes.value(), s);
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} else if (axes.has_value()) {
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return mx::fft::rfftn(a, axes.value(), s);
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} else if (n.has_value()) {
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throw std::invalid_argument(
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"[rfftn] `axes` should not be `None` if `s` is not `None`.");
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} else {
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return mx::fft::rfftn(a, s);
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}
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},
|
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"a"_a,
|
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"s"_a = nb::none(),
|
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"axes"_a = nb::none(),
|
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"stream"_a = nb::none(),
|
|
R"pbdoc(
|
|
n-dimensional real discrete Fourier Transform.
|
|
|
|
The output has the same shape as the input except along the dimensions in
|
|
``axes`` in which case it has sizes from ``s``. The last axis in ``axes`` is
|
|
treated as the real axis and will have size ``s[-1] // 2 + 1``.
|
|
|
|
Args:
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|
a (array): The input array. If the array is complex it will be silently
|
|
cast to a real type.
|
|
s (list(int), optional): Sizes of the transformed axes. The
|
|
corresponding axes in the input are truncated or padded with
|
|
zeros to match the sizes in ``s``. The default value is the
|
|
sizes of ``a`` along ``axes``.
|
|
axes (list(int), optional): Axes along which to perform the FFT.
|
|
The default is ``None`` in which case the FFT is over the last
|
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``len(s)`` axes or all axes if ``s`` is also ``None``.
|
|
|
|
Returns:
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array: The real DFT of the input along the given axes. The output
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)pbdoc");
|
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m.def(
|
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"irfftn",
|
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[](const mx::array& a,
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const std::optional<mx::Shape>& n,
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const std::optional<std::vector<int>>& axes,
|
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mx::StreamOrDevice s) {
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if (axes.has_value() && n.has_value()) {
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return mx::fft::irfftn(a, n.value(), axes.value(), s);
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} else if (axes.has_value()) {
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return mx::fft::irfftn(a, axes.value(), s);
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} else if (n.has_value()) {
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throw std::invalid_argument(
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"[irfftn] `axes` should not be `None` if `s` is not `None`.");
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} else {
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return mx::fft::irfftn(a, s);
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}
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},
|
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"a"_a,
|
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"s"_a = nb::none(),
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"axes"_a = nb::none(),
|
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"stream"_a = nb::none(),
|
|
R"pbdoc(
|
|
The inverse of :func:`rfftn`.
|
|
|
|
Note the input is generally complex. The dimensions of the input
|
|
specified in ``axes`` are padded or truncated to match the sizes
|
|
from ``s``. The last axis in ``axes`` is treated as the real axis
|
|
and will have size ``s[-1] // 2 + 1``.
|
|
|
|
Args:
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a (array): The input array.
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s (list(int), optional): Sizes of the transformed axes. The
|
|
corresponding axes in the input are truncated or padded with
|
|
zeros to match the sizes in ``s``. The default value is the
|
|
sizes of ``a`` along ``axes``.
|
|
axes (list(int), optional): Axes along which to perform the FFT.
|
|
The default is ``None`` in which case the FFT is over the last
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``len(s)`` axes or all axes if ``s`` is also ``None``.
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Returns:
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array: The real array containing the inverse of :func:`rfftn`.
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)pbdoc");
|
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m.def(
|
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"fftshift",
|
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[](const mx::array& a,
|
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const std::optional<std::vector<int>>& axes,
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mx::StreamOrDevice s) {
|
|
if (axes.has_value()) {
|
|
return mx::fft::fftshift(a, axes.value(), s);
|
|
} else {
|
|
return mx::fft::fftshift(a, s);
|
|
}
|
|
},
|
|
"a"_a,
|
|
"axes"_a = nb::none(),
|
|
"stream"_a = nb::none(),
|
|
R"pbdoc(
|
|
Shift the zero-frequency component to the center of the spectrum.
|
|
|
|
Args:
|
|
a (array): The input array.
|
|
axes (list(int), optional): Axes over which to perform the shift.
|
|
If ``None``, shift all axes.
|
|
|
|
Returns:
|
|
array: The shifted array with the same shape as the input.
|
|
)pbdoc");
|
|
m.def(
|
|
"ifftshift",
|
|
[](const mx::array& a,
|
|
const std::optional<std::vector<int>>& axes,
|
|
mx::StreamOrDevice s) {
|
|
if (axes.has_value()) {
|
|
return mx::fft::ifftshift(a, axes.value(), s);
|
|
} else {
|
|
return mx::fft::ifftshift(a, s);
|
|
}
|
|
},
|
|
"a"_a,
|
|
"axes"_a = nb::none(),
|
|
"stream"_a = nb::none(),
|
|
R"pbdoc(
|
|
The inverse of :func:`fftshift`. While identical to :func:`fftshift` for even-length axes,
|
|
the behavior differs for odd-length axes.
|
|
|
|
Args:
|
|
a (array): The input array.
|
|
axes (list(int), optional): Axes over which to perform the inverse shift.
|
|
If ``None``, shift all axes.
|
|
|
|
Returns:
|
|
array: The inverse-shifted array with the same shape as the input.
|
|
)pbdoc");
|
|
}
|