gdalwarp gives different cellsize when re-projected
Hello, Thank you very much for your reply. After some careful reading about GDAL i was able to change the resolution once i re-projected the grid. i used the following command gdalwarp outfile2.tif outfile3.tif -tr 0.05 0.05 outfile2.tif-0.065 resolution outfile3.tif-0.05 resolution Thanks, Navin
On 3/7/13 2:52 PM, Alexandre Villers wrote:
Hello, Well, given you went from a projected to a geographic coordinates system, you changed the unit of the grid from meters to degrees. So I wouldn't be surprised and I guess nothing went wrong as long you specified the correct EPSG for your original file. HTH Alex On 07/03/2013 15:29, Swagath Navin wrote:
Dear all,
I have a large data-frame with Lon, Lat , Value . Coordinates
projected in EPSG:3035 with a resolution of 5 kmx5 km. I converted
this into a SGDF. My goal was to project the file into EPSG:4326 with
a resolution of 0.05. For re-projecting i converted the file to tif
using
writeGDAL(df, "file.tif")
and used the gdalwarp
gdalwarp file.tif outfile.tif -t_srs "+init=epsg:4326"
However while comparing both files the cell size is different.
getGridTopology(file1)
x y
cellcentre.offset 2638500 1430500
cellsize 5000 5000
cells.dim 664 797
projargs: chr " +proj=laea +lat_0=52 +lon_0=10 +x_0=4321000
+y_0=3210000 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs"
getGridTopology(file2)
x y
cellcentre.offset -31.31150705 34.11186136
cellsize 0.06515996 0.06515996
cells.dim 1254.00000000 580.00000000
projargs: chr " +proj=longlat +datum=WGS84 +no_defs +ellps=WGS84
+towgs84=0,0,0"
Can anyone please tell me where it went wrong.
Thanks for your time.
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