Constructs an eulerian
on the complete graph where nodes are integers 1..n. The result in an euler tour for odd n
. For even n
the result is not exactly an euler tour or path because (n-2)/2 edges must be visited twice.
eseq(n)
eseqa(n)
kntour_drop(e)
kntour_add(e)
a numeric vector.
a positive integer.
an euler tour on Kn where n is odd
C.B. Hurley and R.W. Oldford
The algorithm used for eseq builds up a path on 1..n by appending extra edges on to the path on nodes 1..(n-2).
The function eseqa constructs paths on 1..n using an alternative algorithm. For odd n, the tour starts at 1, then takes steps of size 1,2,..m repeatedly, where m is (n-1)/2, For even n, the path constructed is formed as eseqa(n+1), followed by dropping node n+1.
The function kntour_drop removes instances of n from the tour, creating an open approximately eulerian path on the complete graph with n-1 nodes.
The function kntour_add inserts an extra node n+1 into a tour on nodes 1, ..n. It adds a detour to the tour visiting all edges joining nodes 1..n to n+1. The result is an open approximately eulerian path on the complete graph with n+1 nodes.
see overview
hpaths
, eulerian
.
require(PairViz)
eseq(5)
eseq(6)
Run the code above in your browser using DataLab