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I am trying to extract fire data (mean and max fire frequency) for each point within a given buffer size (250m) around multiple points.

Currently, my point data is in Lat and Long.

For the raster data I am planning on using the MODIS burned area products which were derived from the re-projected monthly Geotiff MODIS outputs available from the University of Maryland.

The rest of my data are rasters (WGS 1984 UTM ZONE 38N).

Given that I have these particular data in this format and I want to extract these statistics about them, what is a good strategy for doing it in R?"

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    Your buffer radius is 0.25 degrees, not kilometers. You were explicit about that because your description of the CRS states it uses "longlat" coordinates. You have to deal with several issues to reach your goal, so instead of asking "why doesn't this code work," you would be much better off asking this community a goal-oriented question like "given I have these particular data in this format and I want to extract these statistics about them, what is a good strategy for doing it in R?" – whuber Mar 11 '16 at 15:57
  • using crs_args <- firefrq@crs@projargs in your post does not tell us the actual projection. Can you add it to your post? – MLavoie Mar 12 '16 at 10:30
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You can use raster::extract(r, xy, buffer=250) but you must make sure that the CRS of your points match your raster data (see rgdal::spTransform)

  • Does this work if buffers overlap? – I.Stirs May 30 '16 at 11:32

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