subsetmap {adehabitat} | R Documentation

## Storing a Part of a Map

### Description

`subsetmap` is a generic function. It has methods for the classes `asc` and `kasc`. It is used to store a part of any given map into an other object.

### Usage

    subsetmap(x, xlim = NULL, ylim = NULL, ...)

### Arguments

`x` | an object of class `asc` or `kasc`
`xlim` | numerical vector of length 2. The x limits of the rectangle including the new map
`ylim` | numerical vector of length 2. The y limits of the rectangle including the new map
`...` | further arguments passed to or from other methods

### Details

If `xlim` or `ylim` are not provided, the function asks the user to click on the map to delimit the lower left corner and the higher right corner of the new map (see Examples).

### Value

Returns an object of class `asc` or `kasc`

### Author(s)

Clément Calenge calenge@biomserv.univ-lyon1.fr

### See Also

`as.asc`, `as.kasc`

### Examples

    data(puechabon)
    kasc <- puechabon$kasc
    el <- getkasc(kasc, "Elevation")

    ## limits of the new map:
    xl <- c(701561, 704017)
    yl <- c(3160560, 3162343)

    ## computation of the new map:
    su <- subsetmap(el, xlim = xl, ylim = yl)

    ## Display
    opar <- par(mar = c(0,0,0,0))
    layout(matrix(c(1,1,1,1,1,1,1,1,2), byrow = TRUE, ncol = 3))
    image(el, axes = FALSE)
    polygon(c(xl[1], xl[2], xl[2], xl[1]),
            c(yl[1], yl[1], yl[2], yl[2]))
    image(su, axes = FALSE)
    box()

    par(opar)
    par(mfrow = c(1,1))

    ### Gets this part for the whole kasc object
    m <- subsetmap(kasc, xlim = xl, ylim = yl)
    image(m)

    ## Not run:
     ## Interactive example
     su <- subsetmap(kasc)

     image(su)
    ## End(Not run)

[Package adehabitat version 1.4 Index]