raster

问题 So far I used the following statement in the Raster Calculator of ArcGIS: Con(("Land_use.rst" == -20), "Export.rst") This calculates a new Raster which only contains the Data from Export where Land_use equals -20. That is exactly what I want. But I want to automatise this in R , as I have to do it a lot of times. So far I got something like this: for (catch_dir in Dir_List) { r1 <- raster(paste0(catch_dir, '/Export.rst')) r2 <- raster(paste0(catch_dir,'/LAND_use.rst')) ### statement that

问题 I am using following code for opening a Raster image in single band (with temperature values)- library(raster) nrows = 764 ncols = 1022 df1 <- read.table("AA092800_1.asc", skip = 11, header = FALSE, sep = "\t", dec = ",") r.mat <- matrix(data = "df1", nrow = nrows, ncol = ncols) r <- raster(r.mat) extent(r) <- extent(c(30,45.95,30,45.95)) res(r) plot(r) I am doing a silly mistake and the code is throwing the error- "Error in setValues(r, as.vector(t(x))) : values must be numeric, integer,

问题 I have a data.frame of b/w raster image data that I'm using as a background/base layer. It has three columns: x, y, z. Where x and y are the respective coordinates and z is a continuous value defining a 512 x 512 image. I set this background fill to a black-white gradient and plot using geom_raster() in ggplot2 and then save the image to a PDF file. ### MWE of base layer # original 512x512 data is read in from a file in matrix format, so here's a mocked up example of same: h = matrix(data =

问题 We are building an image editor of sorts using Paper.js. We have a queue on the side of the Paper.js canvas that allows switching between images. Each time we switch between images, we want to flatten all the annotations (rasterize) onto the image just being edited. Each time we switch images, this method is called, which rasterizes the current image and annotations to a data URL. (If we revisit this image, a raster from this data URL will be displayed.) var flattenToDataUrl = function() {

问题 In this Paper.js Sketch, selecting an area of the Mona Lisa raster makes a whiteout Rectangle of the area in place, as well as a generating a subraster of the area. The whiteout rectangle is added first, and the subraster second. However, as you witness in the sketch, the whiteout rectangle remains on top. Test this by commenting out the whiteout rectangle chunk and uncommenting the last line to see that the subraster does indeed get generated. This can be remedied in this scenario with a

问题 I want to combine the SpatialPolygonsDataFrame of two neighbour countries like Pakistan and India. My MWE is below: library(raster) Pakistan.adm1.spdf <- getData( "GADM" , country = "Pakistan" , level = 1 ) India.adm1.spdf <- getData( "GADM" , country = "India" , level = 1 ) How can I combine these two shapefiles? 回答1: From the answer to this question, use rbind and the argument makeUniqueIDs . adm1.spdf <- rbind(Pakistan.adm1.spdf, India.adm1.spdf, makeUniqueIDs = TRUE) plot(adm1.spdf) 来源：

问题 I have Lambert conformal conic projection x,y information. I need the WGS84 coordinate. But I don't know what is lcc exactly. I have provided the lcc information below. Is there a way to convert lcc to WGS84 in r? example lcc x,y : xy <- cbind(c(509535.7, 514535.7),c(201098.6, 201098.6)) lcc information : Latitude of first standard parallel : 30.0 Latitude of second standard parallel : 60.0 Origin latitude : 38.0 Origin longitude : 126.0 Easting of computation point : 43 Northing of

问题 I've looked through all SO but haven't been able to find an answer to this specific question: I have a rasterStack with several layers whose values span over a quite large range. Knowing the values of each layer and the chosen colour scale I believe I have managed to plot all the rasters with the same colour scale, but I face three problems now: I can't be sure that the values are being plotted with the same colour scale, although it seems like it I can't manage to plot the same scale and

问题 For example, A .tiff file of 400*200 size, I can read it as a 2-D array(400 x 200) in python. I want to change the tiff size to 200 x 100 or other ratio. How to realize that in Python or GIS software(QGIS, ArcGIS et.al). I know the resemble tool in ArcGIS can change the size of raster data. but the length-width ratio is fixed. Example Diagram: (source: tietuku.com) 回答1: With R you can do things like library(raster) r <- raster('file.tif') a <- aggregate(r, c(2,3)) 来源： https://stackoverflow

问题 I'm using leaflet for R and I simply would like to be redirected on some URL when I click on the raster image. My current code is the following : library(htmlwidgets) library(raster) library(leaflet) library(sp) imgPath = paste(projectPath,"/test.tif", sep = "") outPath = paste(projectPath, "/leaflethtmlgen.html", sep="") r <- raster(imgPath) pal <- colorNumeric(c("#FF0000", "#666666", "#FFFFFF"), values(r), na.color = "transparent") m <- leaflet() m <- addTiles(m) m <- addRasterImage(m,r,