https://github.com/cran/fields
Tip revision: 04279c16ce718b82025aae97f6fcd30ba3a8b1c5 authored by Doug Nychka on 05 September 2011, 20:18:33 UTC
version 6.6
version 6.6
Tip revision: 04279c1
image.plot.info.R
# fields, Tools for spatial data
# Copyright 2004-2011, Institute for Mathematics Applied Geosciences
# University Corporation for Atmospheric Research
# Licensed under the GPL -- www.gpl.org/licenses/gpl.html
"image.plot.info" <- function(...) {
temp <- list(...)
#
xlim <- NA
ylim <- NA
zlim <- NA
poly.grid <- FALSE
#
# go through various cases of what these can be
#
##### x,y,z list is first argument
if (is.list(temp[[1]])) {
xlim <- range(temp[[1]]$x, na.rm = TRUE)
ylim <- range(temp[[1]]$y, na.rm = TRUE)
zlim <- range(temp[[1]]$z, na.rm = TRUE)
if (is.matrix(temp[[1]]$x) & is.matrix(temp[[1]]$y) &
is.matrix(temp[[1]]$z)) {
poly.grid <- TRUE
}
}
##### check for polygrid first three arguments should be matrices
#####
if (length(temp) >= 3) {
if (is.matrix(temp[[1]]) & is.matrix(temp[[2]]) & is.matrix(temp[[3]])) {
poly.grid <- TRUE
}
}
##### z is passed without an x and y (and not a poly.grid!)
#####
if (is.matrix(temp[[1]]) & !poly.grid) {
xlim <- c(0, 1)
ylim <- c(0, 1)
zlim <- range(temp[[1]], na.rm = TRUE)
}
##### if x,y,z have all been passed find their ranges.
##### holds if poly.grid or not
#####
if (length(temp) >= 3) {
if (is.matrix(temp[[3]])) {
xlim <- range(temp[[1]], na.rm = TRUE)
ylim <- range(temp[[2]], na.rm = TRUE)
zlim <- range(temp[[3]], na.rm = TRUE)
}
}
#### parse x,y,z if they are named arguments
# determine if this is polygon grid (x and y are matrices)
if (is.matrix(temp$x) & is.matrix(temp$y) & is.matrix(temp$z)) {
poly.grid <- TRUE
}
xthere <- match("x", names(temp))
ythere <- match("y", names(temp))
zthere <- match("z", names(temp))
if (!is.na(zthere))
zlim <- range(temp$z, na.rm = TRUE)
if (!is.na(xthere))
xlim <- range(temp$x, na.rm = TRUE)
if (!is.na(ythere))
ylim <- range(temp$y, na.rm = TRUE)
# overwrite zlims with passed values
if (!is.null(temp$zlim))
zlim <- temp$zlim
if (!is.null(temp$xlim))
xlim <- temp$xlim
if (!is.null(temp$ylim))
ylim <- temp$ylim
list(xlim = xlim, ylim = ylim, zlim = zlim, poly.grid = poly.grid)
}