Draw Labeled Vectors in 2D or 3D

Graphics utility functions to draw vectors from an origin to a collection of points (using graphics::arrows() in 2D or rgl::lines3d() in 3D) with labels for each (using graphics::text() or rgl::texts3d()

Usage

vectors(
  x,
  origin = c(0, 0),
  labels = rownames(x),
  scale = 1,
  col = "blue",
  lwd = 1,
  cex = 1,
  length = 0.1,
  angle = 13,
  pos = NULL,
  ...
)

Arguments

x: A two-column matrix or a three-column matrix containing the end points of the vectors
origin: Starting point(s) for the vectors
labels: Labels for the vectors
scale: A multiplier for the length of each vector
col: color(s) for the vectors.
lwd: line width(s) for the vectors.
cex: color(s) for the vectors.
length: For vectors, length of the edges of the arrow head (in inches).
angle: For vectors, angle from the shaft of the arrow to the edge of the arrow head.
pos: For vectors, position of the text label relative to the vector head. If pos==NULL (the default), labels are positioned labels outside, relative to arrow ends
...: other graphical parameters, such as lty, xpd, ...

Value

None

Details

The graphical parameters col, lty and lwd can be vectors of length > 1 and will be recycled if necessary across the rows of x which define the vectors.

For use in high-level plots, vecscale() can be used to find a value for the scale argument to automatically re-scale the vectors to approximately fill the plot region.

The option xpd = TRUE can be passed to vectors() via the ... argument to avoid labels being clipped.

Author

Michael Friendly

Examples


set.seed(1234)
plot(c(-3, 3), c(-3,3), type="n",
     xlab = "X", ylab = "Y")
X <- matrix(rnorm(10), ncol=2)
rownames(X) <- LETTERS[1:5]
vectors(X, scale=2, col=palette(), xpd = TRUE)