How to keep same extent for my 10 raster files?

Question

I am not able to keep same extent for my raster files and stack them together.
library(raster)
# for reproducible example
r1 <- raster(xmn=72.23081, xmx=77.79537, ymn=34.26277, ymx=37.35659,res=1)
values(r1) <- 1:ncell(r1)
r2 <- raster(xmn=72.51037, xmx=77.68996, ymn=34.51186, ymx=37.098,res=1)
values(r2) <- 1:ncell(r2)
r3 <- raster(xmn=72.2514, xmx=77.9430, ymn=34.20765, ymx=37.40778,res=1)
values(r3) <- 1:ncell(r3)

rasters <- list(r1, r2, r3)
s <- stack(rasters)
# Error in compareRaster(x) : different extent

Robert Hijmans · Answer

I already answered your question here.
You have rasters for the same area but with slightly different extents. The first question to ask is why? How were these files generated? They should probably be re-generated so that they do have the same extent. You can also use resample, but then there is some data quality loss. Here is how you can use resample with the example data
for (i in 2:length(rasters)) {
     rasters[[i]] <- resample(rasters[[i]], r1)
} 
s <- stack(rasters)

s
#class      : RasterStack 
#dimensions : 3, 6, 18, 3  (nrow, ncol, ncell, nlayers)
#resolution : 1, 1  (x, y)
#extent     : 72.23081, 78.23081, 34.35659, 37.35659  (xmin, xmax, ymin, ymax)
#crs        : +proj=longlat +datum=WGS84 +no_defs 
#names      :  layer.1,  layer.2,  layer.3 
#min values :  1.00000, -0.57251,  1.28655 
#max values : 18.00000, 13.42749, 18.28655

How to keep same extent for my 10 raster files?

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