Drawing Braids

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(For In[1] see Setup)

In[2]:= ?BraidPlot

BraidPlot[br, opts] produces a plot of the braid br. Possible options are Mode, HTMLOpts and Images.

Thus for example,

In[3]:=

br = BR[5, {{1,3}, {-2,-4}, {1, 3}}];

In[4]:=

Show[BraidPlot[br]]

Drawing Braids Out 4.gif
Out[4]= -Graphics-

BraidPlot takes several options:

In[5]:=

Options[BraidPlot]

Out[5]=
{Mode -> Graphics, Images -> {0.gif, 1.gif, 2.gif, 3.gif, 4.gif}, HTMLOpts -> }

The Mode option to BraidPlot defaults to "Graphics", which produces output as above. An alternative is setting Mode -> "HTML", which produces an HTML <table> that can be readily inserted into HTML documents:

In[6]:=

BraidPlot[br, Mode -> "HTML"]

Out[6]=
<table cellspacing=0 cellpadding=0 border=0>
<tr><td><img src=1.gif><img src=0.gif><img src=1.gif></td></tr>
<tr><td><img src=2.gif><img src=3.gif><img src=2.gif></td></tr>
<tr><td><img src=1.gif><img src=4.gif><img src=1.gif></td></tr>
<tr><td><img src=2.gif><img src=3.gif><img src=2.gif></td></tr>
<tr><td><img src=0.gif><img src=4.gif><img src=0.gif></td></tr>
</table>

The table produced contains an array of image inclusions that together draws the braid using 5 fundamental building blocks: a horizontal "unbraided" line (0.gif above), the upper and lower halves of an overcrossing (1.gif and 2.gif above) and the upper and lower halves of an underfcrossing (3.gif and 4.gif above).

Assuming 0.gif through 4.gif are BraidPart0.gif, BraidPart1.gif, BraidPart2.gif, BraidPart3.gif and BraidPart4.gif, the above table is rendered as follows:

BraidPart1.gifBraidPart0.gifBraidPart1.gif
BraidPart2.gifBraidPart3.gifBraidPart2.gif
BraidPart1.gifBraidPart4.gifBraidPart1.gif
BraidPart2.gifBraidPart3.gifBraidPart2.gif
BraidPart0.gifBraidPart4.gifBraidPart0.gif

The meaning of the Images option to BraidPlot should be clear from reading its default definition:


The HTMLOpts option to BraidPlot allows to insert options within the HTML <img> tags. Thus


The above table is rendered as follows:

BraidPlotHTMLExample2.gif


Thus compare the plots of br1 and br2 below: