search for: spatialpixel

...of the satellite image pixels. I'm asking this because some software packages use the upper left corner of a pixel as a reference. require(sp) # --> Create GRID and image in R S <- SpatialPoints(cbind(spatial["x"], spatial["y"]), proj4string = proj) SP <- SpatialPixels(S, proj4string = proj, tolerance = 5e-07) GRID <- SpatialPixelsDataFrame(points = SP , tolerance = 5e-07, data = spatial[columnname]) proj4string(GRID) <- proj gridded(GRID) nr <- 30 zaxis <- c(0.7, 1) plot(as(GRID, "Spatial"), axes=T) title(m...

This seems pretty basic, but I can't get any data to work except for the documented examples. When the goal is to get to SpatialPixels, here is what I see... > x <- runif(10,1,10) > y <- runif(10,1,10) > z <- rnorm(10,0,1) > MyData <- as.data.frame(cbind(x,y,z)) > library(gstat) > coordinates(MyData) <- ~x + y > gridded(MyData) <- TRUE suggested tolerance minimum: 0.893182669294186 Error i...

...shapefile to a spatial pixel data frame using the sp package by exporting the data from the attribute table in my depth shapefile then importing it into R as a csv file (see my attempts below) >depth<-read.csv("depthmap.csv") >pts = depth[c("x", "y")] >y = SpatialPixels(SpatialPoints(pts)) suggested tolerance minimum: 1 Error in points2grid(points, tolerance, round) : dimension 1 : coordinate intervals are not constant > depth<-read.csv("a.csv") > coordinates(depth) <- c("x", "y") > points2grid(depth) suggested tole...

...rface (I've made a 2-d grid of ground surface values), reverse the log-transformation, and ultimately estimate the total mass of hydrocarbons in the soil. Here's what I've gathered from the supporting documentation: - need to cast the 3-d expected concentration values into sp's SpatialPixelsDataFrame class in order to make any irregular subsets of the rectangular grid. - subsetting the grid probably involves use of "[ ...]" Here's my code so far: library(RODBC) library(gstat) options(digits = 10) channel = odbcDriverConnect("") sqlTables(channel) PAHdata...

...;- reshape(ds, varying=list(1:4), v.names="ndv", direction="long", times=dts, ids=1:dims[1])#traspone le misure in colonne separate dello stesso record in misure ripeture in record diversi library(spacetime) timeIsInterval(dts) <- TRUE stNDVF <- STFDF(as(ndv_gambia, "SpatialPixels"), dts, df) library(RColorBrewer) Grns <- brewer.pal(7, "Greens") -- View this message in context: http://r.789695.n4.nabble.com/timeIsInterval-function-not-found-tp4643906.html Sent from the R help mailing list archive at Nabble.com.

Now I have the forest plot data with x, y locations, and I measured the DBH for every indivicuals. The data looks like that: x=runif(100,0,100) y=runif(100,0,100) dbh=runif(100,1,100) rdata=data.frame(x,y,dbh) > rdata[1:5,] x y dbh 1 99.5354145 1.412844 34.10112 2 0.8259361 87.737036 39.12914 3 6.5678613 65.699032 22.55990 4 67.2987881 72.053877 45.83978 5 2.2491372

I have been using the sp package to deal with gridded data. I would like to know how to extract the vertices (x,y) of polygons that outline areas of like-valued cells in a grid. Here is a simple 3x3 grid: 2 2 1 1 2 1 1 1 3 x <- c(1,1,1,2,2,2,3,3,3) # define a 3 x 3 array of points y <- c(1,2,3,1,2,3,1,2,3) h <- SpatialPoints(cbind(x,y)) # make these an sp object of the points

I imported the attached tiff file and converted the coordinate system to long lat and graphed it: californiatiff<- readGDAL("california1.tif") proj4string(californiatiff) > rasterprojection <- spTransform(californiatiff, CRS("+proj=longlat") however, when using the plot command for rasterprojection, I get a blob. I can see the outline of the state of california and