knotplot {knotR}

Plotting of knots

Description

Routines to plot projections of knots with a wide range of user-settable options

Usage

knotplot(x, ou, gapwidth=1, n=100, lwd=8, add=FALSE, ...)
knotplot_old(x, ou, gap=20, n=100, lwd=8, add=FALSE, ...)
knotplot2(x, rainbow=FALSE, seg=FALSE, text=FALSE, cross=FALSE, ink=FALSE,
                node=FALSE, width=TRUE, all=FALSE, n=100, circ=1000,
                lwd=8, add=FALSE, ...)

Arguments

x

Description of a knot, coerced to a controlpoints object and a minobj object

rainbow, seg, text, cross, ink, node, all, width, circ

Variables controlling sundry knotplot2() features; see details

ou

An overunder object, useful if overunder information not included in argument x

gap, gapwidth

Variables controlling visual representation of strand crossings; see details

n

Number of points on each Bezier curve

lwd

Width of line to use

add

Boolean, with default FALSE meaning to set up a new plot, and TRUE meaning to just add points and lines to an existing plot

...

Further arguments, passed to plot() and points()

Details

Function knotplot() is useful for production-quality plotting of knots with crossings indicated by the understrand having a gap; function knotplot2() is more useful for development. Function knotplot_old() is included for backward compatibility and is possibly more robust than knotplot().

Function knotplot() works by setting a suitable length of the understrand to NA which results in it not being plotted.

For knotplot():

• overunderobj; A two-column matrix indicating the sense of the crossing. Each row corresponds to a crossing; the first entry is the segment number of the overstrand, and the second is the understrand

• gapwidth; the width of the gap, measured in units of width of the string

For knotplot2():

• rainbow; use rainbow colouring for the segments

• seg; plot the Bezier nodes and handles. The positions of the nodes and handles are obtained from an object of class controlpoints.

• text; include the segment number on the segment

• cross; label the crossings

• ink; label the nodes with their inkscape numbering

• width; show the bending strain energy

The gap argument of knotplot_old() is a the same as the gapwidth argument of knotplot() but gap is measured in the same units as the plot().

Author(s)

Robin K. S. Hankin

Examples

knotplot(k5_1)

knotplot2(k6_1,text=TRUE,seg=TRUE,lwd=1)