Plot polygons with arrow heads on each line segment, pointing towards the next vertex. This shows the direction of each line segment.
plotArrows(p, fraction=0.9, length=0.15, first='', add=FALSE, ...)
- Polygons (either a 2 column matrix or data.frame; or a SpatialPolygons* object
- numeric between 0 and 1. When smaller then 1, interrupted lines are drawn
- length of the edges of the arrow head (in inches)
- Character to plot on first (and last) vertex
- Logical. If
TRUE, the plot is added to an existing plot
- Additional arguments, see Details
Based on an example in Software for Data Analysis by John Chambers (pp 250-251) but adjusted such that the line segments follow great circles between vertices.
pol <- rbind(c(-180,-20), c(-160,5), c(-60, 0), c(-160,-60), c(-180,-20)) plotArrows(pol)