Lightly Documented Features

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(For In[1] see Setup)

In[1]:= ?NumberOfKnots

NumberOfKnots[type] return the number of knots of a given type.

In[2]:=
NumberOfKnots[16, NonAlternating]
Out[2]=
1008906
In[3]:= ?MorseLink

MorseLink[K] returns a presentation of the oriented link K, composed, in successive order, of the following 'events': Cup[m,n] is a directed creation, starting at strand position n, towards position m, where m and n differ by 1. X[n,a = {Over/Under}, b = {Up/Down}, c={Up/Down}] is a crossing with lower-left edge at strand n, a determines whether the strand running bottom-left to top-right is over/under the crossing, b and c give the directions of the bottom-left and bottom-right strands respectively through the crossing. Cap[m,n] is a directed cap, from strand m to strand n.

In[4]:= MorseLink::about

MorseLink was added to KnotTheory` by Siddarth Sankaran at the University of Toronto in the summer of 2005.

In[5]:=
MorseLink[Knot[3, 1]]
Out[5]=
MorseLink[1 ? 2, 4 ? 3, X[2, Under, Up, Up], X[2, Under, Up, Up], 
 
  X[2, Under, Up, Up], 2 ? 1, 1 ? 2]
In[6]:= ?DrawMorseLink

DrawMorseLink[L] returns a drawing of the knot or link L as a "Morse Link". For diagrams with a large number of crossings, it may be helpful to use one or both of the options as in DrawMorseLink[L, Gap -> g, ArrowSize -> as ], with 0 < as, g < 1, where g controls the amount of white space at each crossing, and as controls the size of the orientation arrows.

In[7]:= DrawMorseLink::about

DrawMorseLink was written by Siddarth Sankaran at the University of Toronto in the summer of 2005.

In[8]:=
Show[DrawMorseLink[Link[11, Alternating, 548]]]
Lightly Documented Features Out 8.gif
Out[8]= -Graphics-