R: Add Arrows to a Map

mapArrows {oce} | R Documentation

## Add Arrows to a Map

### Description

Plot arrows on an existing map, e.g. to indicate a place location. This is not well-suited for drawing direction fields, e.g. of velocities; for that, see `mapDirectionField`.

### Usage

    mapArrows(longitude0, latitude0, longitude1 = longitude0,
      latitude1 = latitude0, length = 0.25, angle = 30, code = 2,
      col = par("fg"), lty = par("lty"), lwd = par("lwd"), ...)

### Arguments

`longitude0, latitude0` | starting points for arrows.
`longitude1, latitude1` | ending points for arrows.
`length` | length of the arrow heads, passed to `arrows`.
`angle` | angle of the arrow heads, passed to `arrows`.
`code` | numerical code indicating the type of arrows, passed to `arrows`.
`col` | arrow color, passed to `arrows`.
`lty` | arrow line type, passed to `arrows`.
`lwd` | arrow line width, passed to `arrows`.
`...` | optional arguments passed to `arrows`.

### Details

Adds arrows to an existing map, by analogy to `arrows`.

### Author(s)

Dan Kelley

### See Also

A map must first have been created with `mapPlot`.

Other functions related to maps: `lonlat2map`, `lonlat2utm`, `map2lonlat`, `mapAxis`, `mapContour`, `mapDirectionField`, `mapGrid`, `mapImage`, `mapLines`, `mapLocator`, `mapLongitudeLatitudeXY`, `mapPlot`, `mapPoints`, `mapPolygon`, `mapScalebar`, `mapText`, `mapTissot`, `oceCRS`, `shiftLongitude`, `usrLonLat`, `utm2lonlat`

### Examples

    library(oce)
    data(coastlineWorld)
    mapPlot(coastlineWorld, longitudelim=c(-120, -60), latitudelim=c(30, 60),
            col="lightgray", projection="+proj=lcc +lon_0=-100")
    lon <- seq(-120, -75, 15)
    n <- length(lon)
    lat <- 45 + rep(0, n)
    # Draw meridional arrows in N America, from 45N to 60N.
    mapArrows(lon, lat, lon, lat+15, length=0.05, col="blue")

[Package oce version 1.1-1 Index]