Graphical Input

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Thanks to our link with LinKnot, on Windows systems KnotTheory` accepts graphical knot input.

(For In[1] see Setup)

As in the section Using the LinKnot package, the first step is to add LinKnot to the Mathematica search path. This path will likely be different on your computer.

In[2]:= AppendTo[$Path, "C:/bin/LinKnot/"];
In[3]:= ?ConwayNotation
ConwayNotation[s] represents the knot or link whose Conway notation is the string s. ConwayNotation[K], where K is a knot or a link with up to 12 crossings, returns ConwayNotation[s], where s is a string containing the Conway notation of K.
In[4]:= ConwayNotation::about
The program ConwayNotation relies on code from the LinKnot package by Slavik Jablan and Ramila Sazdanovic.

Thus for example, the input line

In[5]:= K = KnotInput[]

pops a blank window on which a knot or a link can be drawn with mouse clicks. At first pass all crossings are drawn as "new over old", but a further click on any given crossing will flip it.

KnotInput in action.

A right click followed by selecting "quit" will then determine the Gauss code of the knot or link just drawn and return it to Mathematica:

Out[5]= GaussCode[{-1,-4,2,3},{-3,-5,4,6},{5,1,-6,-2}]

K is now perfectly usable within KnotTheory`:

In[2]:= AppendTo[$Path, "C:/bin/LinKnot/"];
Out[2]= {{{out}}}