# NOT RUN {
library(grid)
GDALinfo(system.file("external/test.ag", package="sp")[1])
x <- readGDAL(system.file("external/test.ag", package="sp")[1])
class(x)
image(x)
summary(x)
x@data[[1]][x@data[[1]] > 10000] <- NA
summary(x)
image(x)
x <- readGDAL(system.file("external/simple.ag", package="sp")[1])
class(x)
image(x)
summary(x)
x <- readGDAL(system.file("pictures/big_int_arc_file.asc", package="rgdal")[1])
summary(x)
cat("if the range is not 10000, 77590, your GDAL does not detect big\n")
cat("integers for this driver\n")
y = readGDAL(system.file("pictures/Rlogo.jpg", package = "rgdal")[1], band=1)
summary(y)
y = readGDAL(system.file("pictures/Rlogo.jpg", package = "rgdal")[1])
summary(y)
spplot(y, names.attr=c("red","green","blue"),
col.regions=grey(0:100/100),
main="example of three-layer (RGB) raster image", as.table=TRUE)
data(meuse.grid)
gridded(meuse.grid) = ~x+y
proj4string(meuse.grid) = CRS("+init=epsg:28992")
fn <- tempfile()
writeGDAL(meuse.grid["dist"], fn)
GDALinfo(fn)
writeGDAL(meuse.grid["dist"], fn, setStatistics=TRUE)
GDALinfo(fn)
mg2 <- readGDAL(fn)
proj4string(mg2)
SP27GTIF <- readGDAL(system.file("pictures/SP27GTIF.TIF",
package = "rgdal")[1], output.dim=c(100,100))
summary(SP27GTIF)
image(SP27GTIF, col=grey(1:99/100))
GDALinfo(system.file("pictures/cea.tif", package = "rgdal")[1])
GDALSpatialRef(system.file("pictures/cea.tif", package = "rgdal")[1])
cea <- readGDAL(system.file("pictures/cea.tif", package = "rgdal")[1],
output.dim=c(100,100))
summary(cea)
image(cea, col=grey(1:99/100))
fn <- system.file("pictures/erdas_spnad83.tif", package = "rgdal")[1]
erdas_spnad83 <- readGDAL(fn, offset=c(50, 100), region.dim=c(400, 400),
output.dim=c(100,100))
summary(erdas_spnad83)
image(erdas_spnad83, col=grey(1:99/100))
erdas_spnad83a <- readGDAL(fn, offset=c(50, 100), region.dim=c(400, 400))
bbox(erdas_spnad83)
bbox(erdas_spnad83a)
gridparameters(erdas_spnad83)
gridparameters(erdas_spnad83a)
tf <- tempfile()
writeGDAL(erdas_spnad83, tf, drivername="GTiff", type="Byte", options=NULL)
all.equal(erdas_spnad83, readGDAL(tf))
writeGDAL(erdas_spnad83, tf, drivername="GTiff", type="Byte",
options="INTERLEAVE=PIXEL")
all.equal(erdas_spnad83, readGDAL(tf))
writeGDAL(erdas_spnad83, tf, drivername="GTiff", type="Byte",
options=c("INTERLEAVE=PIXEL", "COMPRESS=DEFLATE"))
all.equal(erdas_spnad83, readGDAL(tf))
x <- GDAL.open(system.file("pictures/erdas_spnad83.tif", package = "rgdal")[1])
erdas_spnad83 <- asSGDF_GROD(x, output.dim=c(100,100))
GDAL.close(x)
summary(erdas_spnad83)
image(erdas_spnad83, col=grey(1:99/100))
tf <- tempfile()
xx <- create2GDAL(erdas_spnad83, type="Byte")
xxx <- copyDataset(xx, driver="PNG")
saveDataset(xxx, tf)
GDAL.close(xx)
GDAL.close(xxx)
GDALinfo(tf)
tf2 <- tempfile()
writeGDAL(erdas_spnad83, tf2, drivername="PNG", type="Byte")
GDALinfo(tf2)
GT <- GridTopology(c(0.5, 0.5), c(1, 1), c(10, 10))
set.seed(1)
SGDF <- SpatialGridDataFrame(GT, data=data.frame(z=runif(100)))
opar <- par(mfrow=c(2,2), mar=c(1,1,4,1))
image(SGDF, "z", col=colorRampPalette(c("blue", "yellow"))(20))
title(main="input values")
pfunc <- colorRamp(c("blue","yellow"))
RGB <- pfunc(SGDF$z)
SGDF$red <- RGB[,1]
SGDF$green <- RGB[,2]
SGDF$blue <- RGB[,3]
image(SGDF, red="red", green="green", blue="blue")
title(main="input RGB")
tf <- tempfile()
writeGDAL(SGDF[c("red", "green", "blue")], tf, type="Byte", drivername="PNG")
t1 <- readGDAL(tf)
image(t1, red=1, green=2, blue=3)
title(main="output PNG RGB")
par(opar)
t0 <- meuse.grid["ffreq"]
fullgrid(t0) <- TRUE
t0$ffreq <- as.integer(t0$ffreq)-1
# convert factor to zero-base integer
CT <- c("red", "orange", "green", "transparent")
CT
cN <- c("annual", "2-5 years", "infrequent")
tf <- tempfile()
writeGDAL(t0, tf, type="Byte", colorTable=list(CT), catNames=list(cN),
mvFlag=3L)
attr(GDALinfo(tf, returnStats=FALSE, returnCategoryNames=TRUE),
"CATlist")[[1]]
# }
# NOT RUN {
ds <- GDAL.open(tf)
displayDataset(ds, reset.par=FALSE)
t(col2rgb(getColorTable(ds)[1:4]))
GDAL.close(ds)
# }
# NOT RUN {
fn <- system.file("pictures/test_envi_class.envi", package = "rgdal")[1]
Gi <- GDALinfo(fn, returnColorTable=TRUE, returnCategoryNames=TRUE)
CT <- attr(Gi, "ColorTable")[[1]]
CT
attr(Gi, "CATlist")[[1]]
with <- readGDAL(fn)
with <- readGDAL(fn, silent=TRUE)
table(with$band1)
table(as.numeric(with$band1))
with1 <- readGDAL(fn, as.is=TRUE)
table(with1$band1)
spplot(with, col.regions=CT)
tf <- tempfile()
cN <- levels(with$band1)
with$band1 <- as.integer(with$band1)-1
writeGDAL(with, tf, drivername="ENVI", type="Int16", colorTable=list(CT),
catNames=list(cN), mvFlag=11L)
cat(paste(readLines(paste(tf, "hdr", sep=".")), "\n", sep=""), "\n")
wGi <- GDALinfo(tf, returnColorTable=TRUE, returnCategoryNames=TRUE)
CTN <- attr(wGi, "ColorTable")[[1]]
CTN
attr(wGi, "CATlist")[[1]]
withN <- readGDAL(tf)
table(withN$band1)
withN1 <- readGDAL(tf, as.is=TRUE)
table(withN1$band1)
spplot(withN, col.regions=CTN)
# a file with scale and offset
fn <- system.file("pictures/scaleoffset.vrt", package = "rgdal")[1]
g <- GDALinfo(fn)
attr(g, 'ScaleOffset')
g
fl <- system.file("pictures/MR5905167_372.nc", package="rgdal")[1]
if (file.exists(fl)) {
flstr <- paste0("NETCDF:\"", fl, "\":TEMP")
if ("netCDF" %in% gdalDrivers()$name) GDALinfo(flstr)
}
# }
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