jacentral {nlsr}

jacentral

Description

Approximate Jacobian via central differences. Note this needs two evaluations per parameter, but generally gives much better approximation of the derivatives.

Usage

jacentral(
  pars,
  resfn = NULL,
  bdmsk = NULL,
  resbest = NULL,
  ndstep = 1e-07,
  ...
)

Arguments

pars

a named numeric vector of parameters to the model

resfn

a function to compute a vector of residuals

bdmsk

Vector defining bounds and masks. Default is NULL

resbest

If supplied, a vector of the residuals at the parameters pars to save re-evaluation.

ndstep

A tolerance used to alter parameters to compute numerical approximations to derivatives. Default 1e-7.

...

Extra information needed to compute the residuals

Author(s)

J C Nash 2014-7-16 revised 2022-11-22 nashjc _at_ uottawa.ca