R: Class ATSP - Asymmetric traveling salesperson problem

ATSP {TSP} | R Documentation

## Class ATSP – Asymmetric traveling salesperson problem

### Description

Constructor to create an instance of the asymmetric traveling salesperson problem (ATSP) and some auxiliary methods.

### Usage

    ATSP(x, labels = NULL, method = NULL)

    as.ATSP(x)

    ## S3 method for class 'matrix'
    as.ATSP(x)

    ## S3 method for class 'dist'
    as.ATSP(x)

    ## S3 method for class 'ATSP'
    print(x, ...)

    ## S3 method for class 'ATSP'
    n_of_cities(x)

    ## S3 method for class 'ATSP'
    labels(object, ...)

    ## S3 method for class 'ATSP'
    image(x, order, col = gray.colors(64), ...)

    ## S3 method for class 'ATSP'
    as.matrix(x, ...)

### Arguments

`x, object` | an object (a square matrix) to be converted into an `ATSP` or, for the methods, an object of class `ATSP`.
`labels` | optional city labels. If not given, labels are taken from `x`.
`method` | optional name of the distance metric.
`...` | further arguments are passed on.
`order` | order of cities as an integer vector or an object of class `TOUR`.
`col` | color scheme for image.

### Details

Objects of class `ATSP` are internally represented by a matrix (use `as.matrix()` to get just the matrix).

ATSPs can be transformed into (larger) symmetric TSPs using `reformulate_ATSP_as_TSP()`.

### Value

- `ATSP()` returns `x` as an object of class `ATSP`.

- `n_of_cities()` returns the number of cities in `x`.

- `labels()` returns a vector with the names of the cities in `x`.

### Author(s)

Michael Hahsler

### See Also

Other TSP: `Concorde`, `ETSP()`, `TSPLIB`, `TSP()`, `insert_dummy()`, `reformulate_ATSP_as_TSP()`, `solve_TSP()`

### Examples

    data <- matrix(runif(10^2), ncol = 10, dimnames = list(1:10, 1:10))

    atsp <- ATSP(data)
    atsp

    ## use some methods
    n_of_cities(atsp)
    labels(atsp)

    ## calculate a tour
    tour <- solve_TSP(atsp, method = "nn")
    tour

    tour_length(tour)

    image(atsp, tour)

[Package TSP version 1.2-0 Index]