riffle {partitions} | R Documentation |
Riffle shuffles
Description
Enumeration of riffle shuffles
Usage
genrif(v)
riffle(p,q=p)
Arguments
p , q , v |
In function |
Details
A riffle shuffle is a permutation of integers
1,2,\ldots,n
containing one or two rising
sequences.
A generalized riffle shuffle, or r
-riffle
shuffle, contains at most r
rising sequences. This is not
implemented in the package (earlier versions included a buggy
version; the difficulty is ensuring that sequences do not appear
more than once).
riffle(p,q)
returns all riffle shuffles with rising sequences of1:p
and(p+1):q
genrif(v)
returns all riffle shuffles with rising sequences having lengths the entries ofv
, the deck being numbered consecutively
Value
Returns a matrix of class partition
with columns being
riffle shuffles
Note
When we say “contains r
rising sequences” we generally
mean “contains at most r
rising sequences”
Author(s)
Robin K. S. Hankin
See Also
Examples
riffle(3,4)
genrif(1:3)