ade4 (version 1.2-2)

s.image: 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 line (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

Examples

if (require(splancs, quiet = 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)
}

data(t3012)
if (require(splancs, quiet = TRUE)){
    par(mfrow = c(4,4))
    for(k in 1:12)  s.image(t3012$xy,scalewt(t3012$temp[,k]), kgrid = 3)
    par(mfrow = c(1,1))
}
    
data(elec88)
if (require(splancs, quiet = TRUE)){
   par(mfrow = c(4,4))
   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))
}