fouriax.select_propagator_method#

select_propagator_method(grid, spectrum, distance_um, equality_tolerance=1e-06)#

Select the recommended propagation method for a given distance.

Compares distance_um against the critical distance (see critical_distance_um()) and returns:

  • "asm" when distance_um < z_crit * (1 - equality_tolerance)

  • "rs" otherwise

Parameters:

  • grid (Grid) – Spatial sampling grid.

  • spectrum (Spectrum) – Wavelength set.

  • distance_um (float) – Propagation distance in micrometers (must be positive).

  • equality_tolerance (float) – Relative tolerance around the boundary.

Returns:

"asm" or "rs".

Return type:

str