R: Class ser_permutation_vector - A Single Permutation Vector...

permutation_vector {seriation} | R Documentation

## Class ser_permutation_vector – A Single Permutation Vector for Seriation

### Description

The class `ser_permutation_vector` represents a single permutation vector.

### Usage

    ## constructor
    ser_permutation_vector(x, method = NULL)

### Arguments

`x` | an object which contains a permutation vector (currently an integer vector or an object of class `hclust`). The value `NA` creates an identity permutation.
`method` | a string representing the method used to obtain the permutation vector

### Details

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`.

### Value

An object of class `ser_permutation_vector`.

### Author(s)

Michael Hahsler

### See Also

`ser_permutation`, `get_order`, `get_rank`, `get_permutation_matrix`, `permutation_vector2matrix`.

### Examples

    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

[Package seriation version 1.2-7 Index]