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

### 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()`.

### Author(s)

Dan Kelley

### See Also

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

Other functions related to maps: `formatPosition()`, `lonlat2map()`, `lonlat2utm()`, `map2lonlat()`, `mapAxis()`, `mapContour()`, `mapCoordinateSystem()`, `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 +lat_1=45 +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 1.2-0 Index]