Class ser_permutation_vector – A Single Permutation Vector for Seriation
The class ser_permutation_vector
represents a single permutation vector.
## constructor ser_permutation_vector(x, method = NULL)
x |
an object which contains a permutation vector (currently an
integer vector or an object of class |
method |
a string representing the method used to obtain the permutation vector |
A permutation vector
maps a set of n objects {O_1, O_2, ..., O_n} onto itself.
In seriation we represent a permutation π
as a vector which lists the objects in their permuted order.
For example, the permutation vector <3, 1, 2> indicates that in first position is the object with index 3 then the object with index 1 and finally
the object with index 2.
A permutation vector can be extracted from a permuation vector object
via get_order()
. Such a permutation vector can be directly used
to subset the list of original objects with "["
to apply the permutation.
Note: An alternative way to specify a permutation is via a list of the ranks of the objects after permutation (see get_rank()
).
ser_permutation_vector
objects are usually packed into
a ser_permutation
object
which is a collection of k permutation vectors for k-mode data.
The constructor ser_permutation_vector
checks if the permutation vector is valid
(i.e. if all integers occur exactly once).
The following functions are implemented: print
, rev
,
length
, get_order
, get_rank
, get_method
.
An object of class ser_permutation_vector
.
Michael Hahsler
p <- ser_permutation_vector(sample(10), "random") p ## some methods length(p) get_method(p) get_order(p) get_rank(p) get_permutation_matrix(p) r <- rev(p) r get_order(r) ## create a indentity permutation vector (with unknown length) ip <- ser_permutation_vector(NA) ip
Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.