fire: The FIRE algorithm
In retistruct: Retinal Reconstruction Program

View source: R/fire.R

fire	R Documentation

The FIRE algorithm

Description

This is an implementation of the FIRE algorithm for structural relaxation put forward by Bitzek et al. (2006)

Usage

fire(
  r,
  force,
  restraint,
  m = 1,
  dt = 0.1,
  maxmove = 100,
  dtmax = 1,
  Nmin = 5,
  finc = 1.1,
  fdec = 0.5,
  astart = 0.1,
  fa = 0.99,
  a = 0.1,
  nstep = 100,
  tol = 1e-05,
  verbose = FALSE,
  report = message
)

Arguments

`r`	Initial locations of particles
`force`	Force function
`restraint`	Restraint function
`m`	Masses of points
`dt`	Initial time step
`maxmove`	Maximum distance to move in any time step
`dtmax`	Maximum time step
`Nmin`	Number of steps after which to start increasing `dt`
`finc`	Fractional increase in `dt` per time step
`fdec`	Fractional decrease in `dt` after a stop
`astart`	Starting value of `a` after a stop
`fa`	Fraction of `a` to retain after each step
`a`	Initial value of `a`
`nstep`	Maximum number of steps
`tol`	Tolerance - if RMS force is below this value, stop and report convergence
`verbose`	If `TRUE` report progress verbosely
`report`	Function to report progress when `verbose` is `TRUE`

Value

List containing x, the positions of the points, conv, which is 0 if convergence as occurred and 1 otherwise, and frms, the root mean square of the forces on the particles.