R: Resistance between two arbitrary points on a regular lattice of unit resistors

array.resistance {ResistorArray}

R Documentation

Resistance between two arbitrary points on a regular lattice of unit resistors

Description

Given two points on a regular lattice of electrical nodes joined by unit resistors (as created by makefullmatrix()), returns the resistance between the two points, or (optionally) the potentials of each lattice point when unit current is fed into the first node, and the second is earthed.

Usage

array.resistance(x.offset, y.offset, rows.of.resistors, cols.of.resistors, give.pots = FALSE)

Arguments

`x.offset`	Earthed node is at (0,0), second node is at `(x.offset, y.offset)`
`y.offset`	Earthed node is at (0,0), second node is at `(x.offset, y.offset)`
`rows.of.resistors`	Number of rows of resistors in the network (positive integer)
`cols.of.resistors`	Number of columns of resistors in the network (positive integer)
`give.pots`	Boolean, with `TRUE` meaning to return a matrix of potentials of the electrical nodes, and `FALSE` meaning to return the resistance between the origin and the current input node

Details

Note that the electrical network is effectively toroidal.

Author(s)

Robin K. S. Hankin

Alias

array.resistance

Keyword

array

Examples

jj.approximate <-  array.resistance(1,2,15,17,give=FALSE)
jj.exact <- 4/pi-1/2
print(jj.exact - jj.approximate)

persp(array.resistance(4,0,14,16,give=TRUE),theta=50,r=1e9,expand=0.6)

Results


R version 2.9.0 (2009-04-17)
Copyright (C) 2009 The R Foundation for Statistical Computing
ISBN 3-900051-07-0

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> library(ResistorArray)
> png(filename="images/array.resistance_%03d.png" ,width=480, height=480)
> ### Name: array.resistance
> ### Title: Resistance between two arbitrary points on a regular lattice of
> ###   unit resistors
> ### Aliases: array.resistance
> ### Keywords: array
> 
> ### ** Examples
> 
> jj.approximate <-  array.resistance(1,2,15,17,give=FALSE)
> jj.exact <- 4/pi-1/2
> print(jj.exact - jj.approximate)
[1] 0.01040859
> 
> persp(array.resistance(4,0,14,16,give=TRUE),theta=50,r=1e9,expand=0.6)
> 
> 
> 
> dev.off()
null device 
          1 
>

[Package ResistorArray Index]