smpy.filters.processing.schneider_filter

smpy.filters.processing.schneider_filter(scaled_radii, scale, l=3)

Compute Schneider filter values for given scaled radii.

Calculate the Schneider filter function values with polynomial weighting for aperture mass mapping applications.

Parameters:

• scaled_radii (numpy.ndarray) – Radius values scaled by the aperture radius.

• scale (float) – Scale radius of the filter in pixels.

• l (int, optional) – Polynomial order parameter.

Returns:

filter_values – Q filter values at the given radii positions.

Return type:

numpy.ndarray

Notes

Implements the Schneider et al. (1998) Q function: Q(ϑ) = [(1+ℓ)(2+ℓ)/(πθ²)] * (ϑ²/θ²) * (1-ϑ²/θ²)^ℓ * H(θ-ϑ) where H is the Heaviside function ensuring compact support.

References

[1]

Schneider et al. 1998