R: Class ETSP - Euclidean traveling salesperson problem

ETSP {TSP} | R Documentation

## Class ETSP – Euclidean traveling salesperson problem

### Description

Constructor to create an instance of a Euclidean traveling salesperson problem (TSP) represented by city coordinates and some auxiliary methods.

### Usage

    ETSP(x, labels = NULL)

    as.ETSP(x)

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

    ## S3 method for class 'data.frame'
    as.ETSP(x)

    ## S3 method for class 'ETSP'
    as.TSP(x)

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

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

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

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

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

    ## S3 method for class 'ETSP'
    plot(x, y = NULL, tour = NULL, tour_lty = 2, tour_col = 1, ...)

### Arguments

`x, object` | an object (data.frame or matrix) to be converted into a `ETSP` or, for the methods, an object of class `ETSP`.
`labels` | optional city labels. If not given, labels are taken from `x`.
`...` | further arguments are passed on.
`order` | order of cities for the image as an integer vector or an object of class TOUR.
`col` | color scheme for image.
`tour, y` | a tour to be visualized.
`tour_lty, tour_col` | line type and color for tour.

### Details

Objects of class `ETSP` are internally represented as a `matrix` objects (use `as.matrix()` to get the `matrix` object).

### Value

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

- `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: `ATSP()`, `Concorde`, `TSPLIB`, `TSP()`, `insert_dummy()`, `reformulate_ATSP_as_TSP()`, `solve_TSP()`

### Examples

    x <- data.frame(x = runif(20), y = runif(20), row.names = LETTERS[1:20])

    ## create a TSP
    etsp <- ETSP(x)
    etsp

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

    ## plot ETSP and solution
    tour <- solve_TSP(etsp)
    tour

    plot(etsp, tour, tour_col = "red")

[Package TSP version 1.2-0 Index]