Pensieve header: Computing linking matrices.

<<KnotTheory`

L=Link["L9a1"]

Skeleton[L]

LM[L_]:=Module[{skel=Skeleton[L], lm},
lm=Table[0,{Length@skel},{Length@skel}];
(x|->(lm[[Position[skel,x[[1]]][[1,1]],Position[skel,x[[2]]][[1,1]]]]+=If[PositiveQ[x],1,-1]))/@PD[L];
lm
]

LM[L]//MatrixForm

DrawPD@L

MatrixForm@LM@#&/@AllLinks[9,Alternating]