Merging multiple rasters in R

Question

I\'ve been trying to find a time-efficient way to merge multiple raster images in R. These are adjacent ASTER scenes from the southern Kilimanjaro region, and my target is to pu

Answer 1

I ran into the following problem when trying to mosaic several rasters on top of each other

In vv[is.na(vv)] <- getValues(x[[i]])[is.na(vv)] :
  number of items to replace is not a multiple of replacement length 

As @Robert Hijmans pointed out, it was likely because of misaligned rasters. To work around this, I had to resample the rasters first

library(raster)

x  <- raster("Base_raster.tif")
r1 <- raster("Top1_raster.tif")
r2 <- raster("Top2_raster.tif")

# Resample
x1 <- resample(r1, crop(x, r1))
x2 <- resample(r2, crop(x, r2))

# Merge rasters. Make sure to use the right order
m <- merge(merge(x1, x2), x)

# Write output
writeRaster(m,
            filename = file.path("Mosaic_raster.tif"),
            format = "GTiff",
            overwrite = TRUE)