resource_power_law: Construct the background resource power-law spectrum

In mizer: Dynamic Multi-Species Size Spectrum Modelling

Construct the background resource power-law spectrum

Description

Internal helper returning the auto-calculated resource power law \kappa\, w^{-\lambda} on the full size grid, optionally truncated at an upper cutoff w_max. When the bin_average entry of the model's second_order_w slot is set, the exact bin average of the power law over each bin is returned instead (with the bin straddling w_max getting the partial average), so that the initial resource is the finite-volume cell average of the background spectrum, consistent with the bin-integrated encounter convolution that consumes it as a cell average. Otherwise the left-edge point values are returned, byte-identical to previous mizer.

Usage

resource_power_law(params, kappa, lambda, w_max = Inf)

Arguments

params	A MizerParams object whose second_order_w slot controls the gating and whose w_full/dw_full give the grid.
kappa	The coefficient \kappa of the power law.
lambda	The exponent so the power law is w^{-\lambda}.
w_max	Optional upper cutoff. The power law is taken to be zero at and above w_max. Defaults to Inf (no cutoff).

Details

This is used wherever the background resource spectrum \kappa w^{-\lambda} is constructed from scratch: the initial resource abundance in newMultispeciesParams() and the temporary prey spectra used to compute the default gamma/f0 (get_gamma_default(), get_f0_default()) and the consumer initial abundances (get_initial_n()). The bin-averaged resource capacity and rate are produced directly by setResource().

Value

A numeric vector (same length as w_full) of the resource spectrum.

mizer documentation built on Aug. 31, 2026, 5:08 p.m.