Setup

From Knot Atlas
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Start by downloading either the file KnotTheory.tar.gz (file description) or the file KnotTheory.zip (file description) (around 1MB each), and unpack either one. This will create a subdirectory KnotTheory/ in your current working directory. This done, no installation is required (though you may wish to check out Further Data Files below). Start Mathematica and you're ready to go:

In[1]:= << KnotTheory`

Loading KnotTheory` (version of August 29, 2005, 15:27:48)...

Notice the little "prime" at the end of KnotTheory above. It is a backquote (find it on the upper left side of most keyboards) and not a quote, and it really has to be there for things to work.

Let us check that everything is working well:

In[2]:= Alexander[Knot[6, 2]][t]
Out[2]= -2 3 2 -3 - t + - + 3 t - t t
In[3]:= ?KnotTheoryVersion
KnotTheoryVersion[] returns the date of the current version of the package KnotTheory`. KnotTheoryVersion[k] returns the kth field in KnotTheoryVersion[].
In[4]:= ?KnotTheoryVersionString
KnotTheoryVersionString[] returns a string containing the date and time of the current version of the package KnotTheory`. It is generated from KnotTheoryVersion[].
In[5]:= ?KnotTheoryWelcomeMessage
KnotTheoryWelcomeMessage[] returns a string containing the welcome message printed when KnotTheory` is first loaded.

Thus on the day this manual page was last changed, we had:

In[6]:= {KnotTheoryVersion[], KnotTheoryVersionString[]}
Out[6]= {{2005, 8, 29, 15, 27, 48}, August 29, 2005, 15:27:48}
In[7]:= KnotTheoryWelcomeMessage[]
Out[7]= Loading KnotTheory` (version of August 29, 2005, 15:27:48)...
In[8]:= ?KnotTheoryDirectory
KnotTheoryDirectory[] returns the best guess KnotTheory` has for its location on the host computer. It can be reset by the user.
In[9]:= KnotTheoryDirectory[]
Out[9]= C:/drorbn/KAtlas/\KnotTheory

KnotTheoryDirectory may not work under some operating systems/environments. Please let Dror know if you encounter any difficulties.

Notes

Precomputed Data

KnotTheory` comes with a certain amount of precomputed data which is loaded "on demand" just when it is needed. When a precomputed data file is read by KnotTheory`, a notification message is displayed. To prevent these messages from appearing execute the command Off[KnotTheory::loading].

====Further Data Files==== To access the Hoste-Thistlethwaite enumeration of knots with 12 to 16 crossings (see Naming and Enumeration), also download either the file DTCodes4Knots12To16.tar.gz (file description) or the file DTCodes4Knots12To16.zip (file description) (about 9MB each), and unpack either one into the directory KnotTheory/.