Convert constrained reference-increment coordinates to Linf/K

Map unconstrained parameters to the generalized Schnute growth family while guaranteeing Linf > linf_floor, K > 0, and gamma inside its specified bounds. The lower reference increment is estimated directly (as a bounded fraction of the distance to linf_floor); the second coordinate controls the ratio of transformed growth potentials at the two reference lengths.

Usage

growth_reference_to_linf(
  reference_alpha = 50,
  reference_beta = 80,
  linf_floor,
  alpha_increment_unconstrained,
  asymptote_ratio_unconstrained,
  shape_unconstrained,
  shape_lower = 1,
  shape_upper = 8
)

Arguments

reference_alpha

Lower reference length (mm).

reference_beta

Upper reference length (mm).

linf_floor

Group-specific lower bound for Linf (mm).

alpha_increment_unconstrained

Unconstrained lower-reference increment coordinate.

asymptote_ratio_unconstrained

Unconstrained transformed-potential ratio coordinate.

shape_unconstrained

Unconstrained shape coordinate.

shape_lower

Lower bound for gamma.

shape_upper

Upper bound for gamma.

Value

A list containing linf, k, gshape, the two reference increments, and intermediate annual-fraction coordinates.