Module sleplet.wavelet_methods

Methods to work with wavelet and wavelet coefficients.

Functions

def axisymmetric_wavelet_forward(L: int,
flm: numpy.ndarray[typing.Any, numpy.dtype[numpy.complex128 | numpy.float64]],
wavelets: numpy.ndarray[typing.Any, numpy.dtype[numpy.complex128]]) ‑> numpy.ndarray[typing.Any, numpy.dtype[numpy.complex128]]

Compute the coefficients of the axisymmetric wavelets.

Args

L
The spherical harmonic bandlimit.
flm
The spherical harmonic coefficients.
wavelets
Axisymmetric wavelets.

Returns

Axisymmetric wavelets coefficients.

def axisymmetric_wavelet_inverse(L: int,
wav_coeffs: numpy.ndarray[typing.Any, numpy.dtype[numpy.complex128]],
wavelets: numpy.ndarray[typing.Any, numpy.dtype[numpy.complex128]]) ‑> numpy.ndarray[typing.Any, numpy.dtype[numpy.complex128]]

Compute the inverse axisymmetric wavelet transform.

Args

L
The spherical harmonic bandlimit.
wav_coeffs
Axisymmetric wavelet coefficients.
wavelets
Axisymmetric wavelets.

Returns

Spherical harmonic coefficients of the signal.

def create_kappas(xlim: int, B: int, j_min: int) ‑> numpy.ndarray[typing.Any, numpy.dtype[numpy.float64]]

Compute the Slepian wavelets.

Args

xlim
The x-axis value. L or L^2 in the harmonic or Slepian case.
B
The wavelet parameter. Represented as \lambda in the papers.
j_min
The minimum wavelet scale. Represented as J_{0} in the papers.

Returns

The Slepian wavelet generating functions.

def find_non_zero_wavelet_coefficients(wav_coeffs: numpy.ndarray[typing.Any, numpy.dtype[numpy.complex128 | numpy.float64]],
*,
axis: int | tuple[int, ...]) ‑> numpy.ndarray[typing.Any, numpy.dtype[numpy.complex128 | numpy.float64]]

Find the coefficients within the shannon number to speed up computations.

Args

wav_coeffs
The wavelet coefficients.
axis
The axis to search over.

Returns

The non-zero wavelet coefficients.

def slepian_wavelet_forward(f_p: numpy.ndarray[typing.Any, numpy.dtype[numpy.complex128 | numpy.float64]],
wavelets: numpy.ndarray[typing.Any, numpy.dtype[numpy.float64]],
shannon: int) ‑> numpy.ndarray[typing.Any, numpy.dtype[numpy.complex128 | numpy.float64]]

Compute the coefficients of the given tiling function in Slepian space.

Args

f_p
The Slepian coefficients.
wavelets
The Slepian wavelets.
shannon
The Shannon number.

Returns

The Slepian wavelets coefficients of the signal.

def slepian_wavelet_inverse(wav_coeffs: numpy.ndarray[typing.Any, numpy.dtype[numpy.complex128 | numpy.float64]],
wavelets: numpy.ndarray[typing.Any, numpy.dtype[numpy.float64]],
shannon: int) ‑> numpy.ndarray[typing.Any, numpy.dtype[numpy.complex128 | numpy.float64]]

Compute the inverse wavelet transform in Slepian space.

Args

wav_coeffs
The Slepian wavelet coefficients.
wavelets
The Slepian wavelets.
shannon
The Shannon number.

Returns

The coefficients of the signal in Slepian space.