![]() ![]() # Convert the raster to a data frame with x and y coordinate values in columns # Convert a raster to a data frame and a SpatialPoints If you wish to have coordinates attached to the data frame, you can use the coordinates(.) call. The code below converts a raster that has been loaded into a data frame. PointCoordinates=ame(pointCoordinates,rasValue) # Add the pixel values back into the data frame RasValue=raster::extract(raster1, pointCoordinates) # Extract the values using the coordinates PointCoordinates=read.csv("C:\\Temp3\\LandSatCoordinates.csv")Ĭoordinates(pointCoordinates)= ~ X Y # Convert to a coordinates object # Load a CSV that contains colmns of X and Y coordinate values The code below will extract the pixel values from a raster based on the coordinates in a data frame and then add the pixel values back into the data frame. ![]() WriteRaster(TheRaster, FilePath) Extracting Values from Raster Files It's also easy to write a raster to a new file. FilePath=file.choose()Īgain, R Studio will open the file chooser dialog behind its main window so you may need to minimize it. You can also use a "File Chooser" dialog to open an existing file as follows. AnnualMeanTemp=raster("C:/ProjectsModeling/Cali_5minute/bio_1_AnnualMeanTemp_2.img")ĪnnualMeanTemp=raster("C:/ProjectsModeling/Cali_5minute/DEM.tif") Once you have the libraries loaded it is easy to read an existing raster file. Progress bars and error messages may appear behind R Studio so you may want to minimize it or move it out of the way.Īfter installing the packages, load the libraries. Installing these packages may also load a series of other libraries and it will take a while. This includes TIFF, GeoTIFF, IMG, and over 100 others. "Raster" contains a set of classes for working with raster data and "rgal" includes the GDAL OpenSource library for reading and writing Geospatial file formats. Install the "raster" and "rgdal" packages. ![]() terra is a potential replacement () Required Packages Note that rgdal is supposed to go away in 2023. Once you read or create a raster, you can use it as you would other vectors and matricies. R has the ability to read raster file formats but you'll need to install some additional packages. ![]()
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