rustmatrix.tmatrix_aux

Auxiliary constants and drop-shape relationships.

Direct port of pytmatrix.tmatrix_aux. Wavelength presets (radar bands), typical K_w^2 factors, canned geometries for backscatter / forward-scatter, and the Thurai/Pruppacher-Beard/Beard-Chuang drop axis-ratio formulas.

rustmatrix.tmatrix_aux.dsr_thurai_2007(D_eq)

Thurai et al. (2007) equilibrium raindrop axis ratio (v/h).

Parameters:

D_eq (float) – Equivalent (volume) diameter in mm.

Returns:

Vertical / horizontal axis ratio (≤ 1 for flattened drops). Scatterer expects horizontal / vertical, so pass 1.0 / dsr_thurai_2007(D) as axis_ratio.

Return type:

float

References

Thurai, M. et al. (2007). Drop shapes, model comparisons, and calculations of polarimetric radar parameters in rain. J. Atmos. Oceanic Technol., 24, 1019–1032.

rustmatrix.tmatrix_aux.dsr_pb(D_eq)

Pruppacher & Beard linear drop-shape relation (v/h).

Parameters:

D_eq (float) – Equivalent diameter in mm.

Returns:

1.03 - 0.062 D. Use 1 / dsr_pb(D) as Scatterer.axis_ratio.

Return type:

float

rustmatrix.tmatrix_aux.dsr_bc(D_eq)

Beard & Chuang drop-shape relation (v/h).

Parameters:

D_eq (float) – Equivalent diameter in mm.

Returns:

Fourth-order polynomial fit to the Beard & Chuang (1987) equilibrium shapes. Use 1 / dsr_bc(D) as Scatterer.axis_ratio.

Return type:

float