s.image: Graph of a variable using image and contour

In ade4: Analysis of Ecological Data: Exploratory and Euclidean Methods in Environmental Sciences

Graph of a variable using image and contour

Description

performs a scatterplot

Usage

s.image(dfxy, z, xax = 1, yax = 2, span = 0.5, xlim = NULL, ylim = NULL, 
  kgrid = 2, scale = TRUE, grid = FALSE, addaxes = FALSE, cgrid = 0, 
  include.origin = FALSE, origin = c(0, 0), sub = "", csub = 1, 
  possub = "topleft", neig = NULL, cneig = 1, image.plot = TRUE, 
  contour.plot = TRUE, pixmap = NULL, contour = NULL, area = NULL, 
  add.plot = FALSE)

Arguments

dfxy	a data frame containing the two columns for the axes
z	a vector of values on the dfxy rows
xax	the column number of x in dfxy
yax	the column number of y in dfxy
span	the parameter alpha which controls the degree of smoothing
xlim	the ranges to be encompassed by the x-axis, if NULL they are computed
ylim	the ranges to be encompassed by the y-axis, if NULL they are computed
kgrid	a number of points used to locally estimate the level line through the nodes of the grid, used by kgrid*sqrt(length(z))
scale	if TRUE, data are centered and reduced
grid	if TRUE, the background grid is traced
addaxes	a logical value indicating whether the axes should be plotted
cgrid	a character size, parameter used with par("cex")* cgrid to indicate the mesh of the grid
include.origin	a logical value indicating whether the point "origin" should be belonged to the graph space
origin	the fixed point in the graph space, for example c(0,0) the origin axes
sub	a string of characters to be inserted as legend
csub	a character size for the legend, used with par("cex")*csub
possub	a string of characters indicating the sub-title position ("topleft", "topright", "bottomleft", "bottomright")
neig	an object of class neig
cneig	a size for the neighbouring graph lines used with par("lwd")*cneig
image.plot	if TRUE, the image is traced
contour.plot	if TRUE, the contour lines are plotted
pixmap	an object 'pixmap' displayed in the map background
contour	a data frame with 4 columns to plot the contour of the map : each row gives a segment (x1,y1,x2,y2)
area	a data frame of class 'area' to plot a set of surface units in contour
add.plot	if TRUE uses the current graphics window

Value

The matched call.

Author(s)

Daniel Chessel

Examples

if(!adegraphicsLoaded()) {
  if(requireNamespace("splancs", quietly = TRUE)) {
    wxy <- data.frame(expand.grid(-3:3, -3:3))
    names(wxy) <- c("x", "y")
    z <- (1 / sqrt(2)) * exp(-(wxy$x ^ 2 + wxy$y ^ 2) / 2)
    par(mfrow = c(2, 2))
    s.value(wxy, z)
    s.image(wxy, z)
    s.image(wxy, z, kgrid = 5)
    s.image(wxy, z, kgrid = 15)
    par(mfrow = c(1, 1))
  }
  
  ## Not run: 
  data(t3012)
  if(requireNamespace("splancs", quietly = TRUE)) {
    par(mfrow = c(3, 4))
    for(k in 1:12)
      s.image(t3012$xy, scalewt(t3012$temp[, k]), kgrid = 3)
    par(mfrow = c(1, 1))
  }
      
  data(elec88)
  if(requireNamespace("splancs", quietly = TRUE)) {
    par(mfrow = c(3,4))
    for(k in 1:12)
      s.image(t3012$xy, scalewt(t3012$temp[, k]), kgrid = 3, sub = names(t3012$temp)[k],
        csub = 3, area = elec88$area)
    par(mfrow = c(1, 1))
  }
  
## End(Not run)
}

ade4 documentation built on Feb. 16, 2023, 7:58 p.m.