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maps (version 3.3.0)

identify.map: Identify regions on a map

Description

Identifies the map regions clicked by the user.

Usage

# S3 method for map
identify(x, n = 1, index = FALSE, ...)

Arguments

x

a map object containing named polygons.

n

the number of clicks to wait for.

index

If TRUE, returns the index of the polygon, rather than its name.

...

additional arguments passed to identify.default.

Value

a character vector of length n, naming the selected regions.

Details

The current algorithm is somewhat crude --- selects the region whose centroid is closest to the click. A more sophisticated approach would use map.where.

See Also

identify, map.where

Examples

Run this code
# NOT RUN {
identify(map("state", fill = TRUE, col = 0))
if(require(mapproj))
  identify(map("world", proj = "lagrange", fill = TRUE, col = 0, wrap=c(-180,180,-90)))
# }

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