Extract Raster Values from Points
The R blog article encourages me to write this solution to extract Raster values from points in R. In geospatial analysis, extracting the raster value of a point is a common task. If you have few raster files or few points; you can extract the raster value by overlaying a point on the top of the raster using ArcGIS. What will you do, if you have hundreds of raster files and thousands of points? The easy solution is use loop in Python and ArcGIS. Is loop efficient to use? No. Can loop be avoided? Yes. Then how? Follow the steps: Step 1: Create a Raster stack or Raster brick of your raster files using “raster” package in R . For example: rasStack = stack(raster1, raster2,raster3 …rasterN) Step 2: Read point data, and convert them into spatial points data frame. Sample: pointfile.csv Point_ID LONGITUDE LATITUDE 1 48.765863 -...