contourplot2-methods {copula}R Documentation

Contour Plot Methods 'contourplot2' in Package 'copula'

Description

Methods for contourplot2(), a version of contourplot() from lattice, to draw contour plots of two dimensional distributions from package copula.

Usage

## NB: The 'matrix' and 'data.frame' methods are identical - documenting the former
## S4 method for signature 'matrix'
contourplot2(x, aspect = 1,
      xlim = range(x[,1], finite = TRUE),
      ylim = range(x[,2], finite = TRUE),
      xlab = NULL, ylab = NULL,
      cuts = 16, labels = !region, pretty = !labels,
      scales = list(alternating = c(1,1), tck = c(1,0)),
      region = TRUE, ...,
      col.regions = gray(seq(0.4, 1, length.out = max(100, 4*cuts))))

## S4 method for signature 'Copula'
contourplot2(x, FUN, n.grid = 26, delta = 0,
      xlim = 0:1, ylim = 0:1,
      xlab = quote(u[1]), ylab = quote(u[2]), ...)
## S4 method for signature 'mvdc'
contourplot2(x, FUN, n.grid = 26, xlim, ylim,
      xlab = quote(x[1]), ylab = quote(x[2]), ...)

Arguments

x

a "matrix", "data.frame", "Copula" or a "mvdc" object.

aspect

the aspect ratio.

xlim, ylim

the x- and y-axis limits.

xlab, ylab

the x- and y-axis labels. If at least one is NULL, useful xlab and ylab are determined automatically; the behavior depends on the class of x.

cuts

the number of levels; see contourplot(). Note that specifying useRaster = TRUE is often considerably more efficient notably for larger values of cuts.

labels, pretty

logicals indicating whether the contour lines are labeled and whether pretty labels are enforced; in copula versions before 0.999-18, implicitly pretty = TRUE was used (giving unequal z-cut spacing), see contourplot().

scales

a list determining how the axes are drawn; see contourplot().

region

a logical indicating whether regions between contour lines should be filled as in a level plot; see contourplot().

col.regions

the colors of the regions if region = TRUE; see contourplot().

FUN

the function to be plotted; typically dCopula or pCopula.

n.grid

the number of grid points used in each dimension. This can be a vector of length two, giving the number of grid points used in x- and y-direction, respectively; the function FUN will be evaluated on the corresponding (x,y)-grid.

delta

a small number in [0, \frac 1 2) influencing the evaluation boundaries. The x- and y- vectors will have the range [0+delta, 1-delta], the default being [0,1].

...

additional arguments passed to the underlying contourplot().

Value

An object of class “trellis” as returned by contourplot().

Methods

Contourplot plots for objects of class "matrix" , "data.frame", "Copula" or "mvdc".

See Also

The contour-methods for drawing perspective plots via base graphics.

The lattice-based wireframe2-methods for functions, and cloud2-methods and splom2-methods for data.

Examples

## For 'matrix' objects
## The Frechet--Hoeffding bounds W and M
n.grid <- 26
u <- seq(0, 1, length.out = n.grid)
grid <- expand.grid("u[1]" = u, "u[2]" = u)
W <- function(u) pmax(0, rowSums(u)-1) # lower bound W
M <- function(u) apply(u, 1, min) # upper bound M
x.W <- cbind(grid, "W(u[1],u[2])" = W(grid)) # evaluate W on 'grid'
x.M <- cbind(grid, "M(u[1],u[2])" = M(grid)) # evaluate M on 'grid'
contourplot2(x.W) # contour plot of W
contourplot2(x.M) # contour plot of M

## For 'Copula' objects
cop <- frankCopula(-4)
contourplot2(cop, pCopula) # the copula
contourplot2(cop, pCopula, xlab = "x", ylab = "y") # adjusting the labels
contourplot2(cop, dCopula) # the density

## For 'mvdc' objects
mvNN <- mvdc(gumbelCopula(3), c("norm", "norm"),
             list(list(mean = 0, sd = 1), list(mean = 1)))
xl <- c(-2, 2)
yl <- c(-1, 3)
contourplot2(mvNN, FUN = dMvdc, xlim = xl, ylim = yl, contour = FALSE)
contourplot2(mvNN, FUN = dMvdc, xlim = xl, ylim = yl)
contourplot2(mvNN, FUN = dMvdc, xlim = xl, ylim = yl, region = FALSE, labels = FALSE)
contourplot2(mvNN, FUN = dMvdc, xlim = xl, ylim = yl, region = FALSE)
contourplot2(mvNN, FUN = dMvdc, xlim = xl, ylim = yl,
             col.regions = colorRampPalette(c("royalblue3", "maroon3"), space="Lab"))

[Package copula version 1.1-3 Index]