I would like to extract the time series from a NetCDF file for several points (lat, lon, combinations). How could I do that, so that the lat lon values are read each time from a .csv file?
library(raster) b <- brick("myncfile.nc", varname = "myvar_in_myncfile") pts <- read.csv("my_csvfile.csv", stringsAsFactors = FALSE) ts <- extract(b, cbind(pts$lon, pts$lat))
That will give a
n-time-steps matrix with the extracted values, assuming your NetCDF variable is oriented (lon, lat, time).
But this is just code-guessing, since we have no details about your file/s. You can give a lot of detail by doing
print(b) print(raster("myncfile.nc")) ## provides the ncdump -h print
and telling us the contents. obviously you need to insert your actual file names, and variable name, and column names as appropriate.