On 07/13/2013 01:44 AM, Robert J. Hijmans wrote:
I do not the data have changed. Wrong min and max values are reported, however. Seems to me that in this case gdal does not know the min and max values but reports -2147483648, 2147483647. You could check with GDALinfo. I guess that this is a shortcoming of (your version of?) gdal, not rgdal. Robert
Just in case still be useful.I tried to reproduce the wrongly reported values for min and max using an .asc file I'm using, but I couldn't:
------------ START -----------
library(raster)
# entering to the directory where the .asc file is stored
# setwd("~")
# Creation of a raster file for testing
r <- raster("temp2.asc")
# rgdal: version: 0.8-10, (SVN revision 478)
# Geospatial Data Abstraction Library extensions to R successfully loaded
# Loaded GDAL runtime: GDAL 1.9.2, released 2012/10/08
# Path to GDAL shared files: /usr/share/gdal
# Loaded PROJ.4 runtime: Rel. 4.8.0, 6 March 2012, [PJ_VERSION: 480]
# Path to PROJ.4 shared files: (autodetected)
# Summary of the original raster file
summary(r)
# temp2
# Min. 2.668977e-02
# 1st Qu. 1.474479e-01
# Median 2.109602e-01
# 3rd Qu. 4.575650e-01
# Max. 7.108980e+00
# NA's 1.690500e+04
# Writing the raster from memory to disk (as a new file)
writeRaster(r, filename="temp2_new.asc", format="ascii",overwrite=TRUE)
# class : RasterLayer
# dimensions : 254, 262, 66548 (nrow, ncol, ncell)
# resolution : 5000, 5000 (x, y)
# extent : -1045000, 265000, -620000, 650000 (xmin, xmax, ymin, ymax)
# coord. ref. : NA
# data source : /home/hzambran/temp2_new.asc
# names : temp2_new
# reading the .asc file form disk
r2 <- raster("temp2_new.asc")
# Summary of the .asc file in the hard disk
summary(r2)
# temp2_new
# Min. 2.668977e-02
# 1st Qu. 1.474479e-01
# Median 2.109602e-01
# 3rd Qu. 4.575650e-01
# Max. 7.108980e+00
# NA's 1.690500e+04
# the same summary values are the same as for the original raster (r)
------------ END -----------
I'm using the same rgdal version of Manuel (0.8-10), so as Roger
mentioned before, the error should come from your GDAL version. I'm
using GDAL 1.9.2, released 2012/10/08 (not the latest...)
Kind regards, Mauricio -- ================================================= Water Resources Unit Institute for Environment and Sustainability (IES) Joint Research Centre (JRC), European Commission webinfo : http://floods.jrc.ec.europa.eu/ ================================================= DISCLAIMER: "The views expressed are purely those of the writer and may not in any circumstances be regarded as sta- ting an official position of the European Commission" ================================================= "The journey is the reward" (Steve Jobs)
On Thu, Jul 11, 2013 at 5:04 AM, Manuel Spínola <mspinol...@gmail.com> wrote:Thank you Mauricio.sessionInfo()R version 3.0.1 (2013-05-16) Platform: x86_64-apple-darwin10.8.0 (64-bit) locale: [1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8 attached base packages: [1] grid stats graphics grDevices utils datasets methods base other attached packages: [1] SDMTools_1.1-13 dismo_0.8-11 raster_2.1-37 rgdal_0.8-10 maptools_0.8-25 [6] lattice_0.20-15 sp_1.0-11 foreign_0.8-54 loaded via a namespace (and not attached): [1] tools_3.0.1 2013/7/11 Mauricio Zambrano-Bigiarini <mauricio.zambr...@jrc.ec.europa.eu>On 10/07/13 18:38, Manuel Spínola wrote:Dear list members, I am trying to export a raster file to a ascii file (.asc) but the min and max values are not the same. Any idea why?Hi Manuel, Could you provide your sessionInfo() ?bio1resclass : RasterLayer dimensions : 382, 407, 155474 (nrow, ncol, ncell) resolution : 0.008333333, 0.008333333 (x, y) extent : -85.95, -82.55833, 8.041667, 11.225 (xmin, xmax, ymin, ymax) coord. ref. : NA data source : in memory names : bio1_23 values : 47, 272 (min, max) writeRaster(bio1res, filename="temp.asc", format="ascii",overwrite=TRUE)class : RasterLayer dimensions : 382, 407, 155474 (nrow, ncol, ncell) resolution : 0.008333333, 0.008333333 (x, y) extent : -85.95, -82.55833, 8.041667, 11.225 (xmin, xmax, ymin, ymax) coord. ref. : NA data source : /Users/manuelspinola/Dropbox/**DistribucioÌ n de especies/World_Clim_Costa_**Rica/temp.asc names : temp values : -2147483648, 2147483647 (min, max)Unfortunately, your example is not reproducible, so I tried with a different example and the values in the original and the written ascii file were the same (rgdal_0.8-10, raster_2.1-48, sp_1.0-11): ---------- START -------------- library(raster) Loading required package: sp # Creation of a raster file for testing r <- raster(system.file("external/**test.grd", package="raster")) r #class : RasterLayer #dimensions : 115, 80, 9200 (nrow, ncol, ncell) #resolution : 40, 40 (x, y) #extent : 178400, 181600, 329400, 334000 (xmin, xmax, ymin, ymax) #coord. ref. : +init=epsg:28992 +towgs84=565.237,50.0087,465.** 658,-0.406857,0.350733,-1.**87035,4.0812 +proj=sterea +lat_0=52.15616055555555 +lon_0=5.38763888888889 +k=0.9999079 +x_0=155000 +y_0=463000 +ellps=bessel +units=m +no_defs #data source : /usr/lib64/R/library/raster/**external/test.grd #names : test #values : 128.434, 1805.78 (min, max) writeRaster(r, filename="temp.asc", format="ascii",overwrite=TRUE) #rgdal: version: 0.8-10, (SVN revision 478) #Geospatial Data Abstraction Library extensions to R successfully loaded #Loaded GDAL runtime: GDAL 1.9.2, released 2012/10/08 #Path to GDAL shared files: /usr/share/gdal #Loaded PROJ.4 runtime: Rel. 4.8.0, 6 March 2012, [PJ_VERSION: 480] #Path to PROJ.4 shared files: (autodetected) #class : RasterLayer #dimensions : 115, 80, 9200 (nrow, ncol, ncell) #resolution : 40, 40 (x, y) #extent : 178400, 181600, 329400, 334000 (xmin, xmax, ymin, ymax) #coord. ref. : NA #data source : /home/zambrhe/temp.asc #names : temp # reading the .asc file form disk r2 <- raster("temp.asc") r2 #class : RasterLayer #dimensions : 115, 80, 9200 (nrow, ncol, ncell) #resolution : 40, 40 (x, y) #extent : 178400, 181600, 329400, 334000 (xmin, xmax, ymin, ymax) #coord. ref. : NA #data source : /home/zambrhe/temp.asc #names : temp # Summary of the ascii file in the hard disk #summary(r2) # temp #Min. 128.4340 #1st Qu. 293.2325 #Median 371.4120 #3rd Qu. 499.8195 #Max. 1805.7800 #NA's 6097.0000 # Summary of the original raster file summary(r) # test #Min. 128.4340 #1st Qu. 293.2325 #Median 371.4120 #3rd Qu. 499.8195 #Max. 1805.7800 #NA's 6097.0000 ---------- END -------------- Kind regards, Mauricio Zambrano-Bigiarini, Ph.D -- ==============================**=================== Water Resources Unit Institute for Environment and Sustainability (IES) Joint Research Centre (JRC), European Commission TP 261, Via Enrico Fermi 2749, 21027 Ispra (VA), IT Work Phone : +39 0332 789588 webinfo : http://floods.jrc.ec.europa.**eu/<http://floods.jrc.ec.europa.eu/> ==============================**=================== DISCLAIMER: "The views expressed are purely those of the writer and may not in any circumstances be regarded as sta- ting an official position of the European Commission" ==============================**=================== "The journey is the reward" (Steve Jobs) _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo-- *Manuel Spínola, Ph.D.* Instituto Internacional en Conservación y Manejo de Vida Silvestre Universidad Nacional Apartado 1350-3000 Heredia COSTA RICA mspin...@una.ac.cr mspinol...@gmail.com Teléfono: (506) 2277-3598 Fax: (506) 2237-7036 Personal website: Lobito de río <https://sites.google.com/site/lobitoderio/> Institutional website: ICOMVIS <http://www.icomvis.una.ac.cr/> [[alternative HTML version deleted]] _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
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