plot3D (version 1.0-1)

3-D contours: Contours in 3-D plots.

Description

contour3D adds a contour in a 3-D plot.

Usage

contour3D (x = NULL, y = NULL, z = NULL, 
       ..., colvar = NULL, phi = 40, theta = 40,
       col = NULL, colkey = NULL, 
       panel.first = NULL, clim = NULL, clab = NULL, bty = "b", 
       dDepth = 1e-1, addbox = TRUE, add = FALSE, plot = TRUE)

Arguments

x, y, z

Matrix (2-D), vector, or one value containing the values where the image is to be plotted. At least one of them should be one number, as this will determine where the image is plotted, parallel to the (y-z) plane (x one number), to

colvar

The variable used for coloring. Values of colvar equal to NULL, NA, or FALSE will toggle off coloration according to colvar. This gives good results only if border

col

Color palette to be used for the colvar variable. If col is NULL and colvar is specified, then a red-yellow-blue colorscheme (jet.col) will be used. If

colkey

A logical, NULL (default), or a list with parameters for the color key (legend). List parameters should be one of side, plot, length, width, dist, shift, addlines, col.clab, cex.clab, side.clab, line.clab

clab

Only if colkey = TRUE, the label to be written on top of the color key. The label will be written at the same level as the main title. to lower it, clab can be made a vector, with the first values empty strings.

clim

Only if colvar is specified, the range of the color variable, used for the color key. Values of colvar that extend the range will be put to NA.

theta, phi

The angles defining the viewing direction. theta gives the azimuthal direction and phi the colatitude. see persp.

panel.first

A function to be evaluated after the plot axes are set up but before any plotting takes place. This can be useful for drawing background grids or scatterplot smooths. The function should have as argument the transformation m

bty

The type of the box, the default only drawing background panels. Only effective if the persp argument (box) equals TRUE (this is the default). See pers

dDepth

When a contour is added on an image, the image polygons may hide some contour segments. To avoid that, the viewing depth of the segments can be artificially decreased with the factor dDepth times the

addbox

If TRUE will draw a box around the plot.

add

Logical. If TRUE, then the contours will be added to the current plot. If FALSE a new plot is started.

plot

Logical. If TRUE (default), a plot is created, otherwise the viewing transformation matrix is returned (as invisible).

...

additional arguments passed to the plotting methods. The following persp arguments can be specified: xlim, ylim, zlim, xlab, ylab, zlab, main, sub, r, d, scale, expand, box, axes, nticks, ticktyp

Value

• Returns the viewing transformation matrix. See trans3D.

See Also

contour for R's 2-D contour function.

Examples

# save plotting parameters
 pm <- par("mfrow")

## =======================================================================
## Contours
## =======================================================================
 par (mfrow = c(2, 2))

 r <- 1:nrow(volcano)
 c <- 1:ncol(volcano)
 contour3D(x = r, y = c, z = 100, colvar = volcano, zlim = c(0, 150),
   clab = c("height", "m"))

 contour3D(x = 100, y = r, z = c, colvar = volcano, clab = c("height", "m"))

 contour3D(z = volcano, colvar = volcano, lwd = 2, 
   nlevels = 20, clab = c("height", "m"), colkey = FALSE)

 contour3D(y = volcano, colvar = volcano, lwd = 2, 
   nlevels = 10, clab = c("height", "m"))

## =======================================================================
## Composite images and contours in 3D
## =======================================================================
 persp3D(z = volcano, zlim = c(90, 300), col = "white", 
         shade = 0.1, d = 2, plot = FALSE)
 contour3D(z = volcano, colvar = volcano, lwd = 2, add = TRUE, 
         nlevels = 20, clab = c("height", "m"), plot = FALSE,
         colkey = list(at = seq(90, 190, length.out = 5)))
 contour3D(z = 300, colvar = volcano, lwd = 2, col = "grey",
         add = TRUE, nlevels = 5)
          
## =======================================================================
## the viewing depth of contours (dDepth)
## =======================================================================

# too low
 persp3D(z = volcano, col = "white", shade = 0.1, plot = FALSE)
 contour3D(z = volcano, colvar = volcano, lwd = 2, 
         add = TRUE, dDepth = 0, col = "black")

# default
 persp3D(z = volcano, col = "white", shade = 0.1, plot = FALSE)
 contour3D(z = volcano, colvar = volcano, lwd = 2, 
         add = TRUE, dDepth = 0.1, col = "black")

# too high
 persp3D(z = volcano, col = "white", shade = 0.1, plot = FALSE)
 contour3D(z = volcano, colvar = volcano, lwd = 1, 
         add = TRUE, dDepth = 0.5, col = "black")

# reset plotting parameters
 par(mfrow = pm)