get_range_df_niche: Generate reasonable ranges for starting parameters (math...

In xnicher: Estimates Ecological Niche Models Using Ellipses

Generate reasonable ranges for starting parameters (math scale)

Description

Ensures that env_data is strictly numeric before computing ranges. This prevents downstream issues in Sobol designs and multi-start optimization (e.g., character / factor leakage).

Usage

get_range_df_niche(
  env_data,
  quant_vec = c(0.1, 0.5, 0.9),
  skew = FALSE,
  skew_t = FALSE
)

Arguments

env_data	Numeric matrix or data frame of environmental values.
quant_vec	Numeric vector of quantiles (length 3).
skew	Logical. If TRUE, append p skew parameters (alpha_1, ..., alpha_p) to the parameter vector with the default Sobol range [-3, 0, 3]. Default FALSE keeps the Gaussian-only parameterization.
skew_t	Logical. If TRUE, append a single log_r parameter (degrees-of-freedom for the multivariate non-central skew-t) AFTER the alpha block. The Sobol range is [log 2, log 10, log 100]; the optimizer is then free to move log_r anywhere on the real line. Implies skew = TRUE.

Value

A data frame with rows = parameter names and columns lower, center, upper.

xnicher documentation built on Sept. 15, 2026, 5:08 p.m.