| mapArrows {oce} | R Documentation |
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.
mapArrows(longitude0, latitude0, longitude1 = longitude0,
latitude1 = latitude0, length = 0.25, angle = 30, code = 2,
col = par("fg"), lty = par("lty"), lwd = par("lwd"), ...)
longitude0, latitude0 |
starting points for arrows. |
longitude1, latitude1 |
ending points for arrows. |
length |
length of the arrow heads, passed to |
angle |
angle of the arrow heads, passed to |
code |
numerical code indicating the type of arrows, passed to |
col |
arrow color, passed to |
lty |
arrow line type, passed to |
lwd |
arrow line width, passed to |
... |
optional arguments passed to |
Adds arrows to an existing map, by analogy to arrows.
Dan Kelley
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
## Not run:
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")
## End(Not run)