id,summary,reporter,owner,description,type,status,priority,milestone,component,version,resolution,keywords,cc,cpu,platform 2854,results in winGRASS7 32bit vs 64bit: should they be identical?,hellik,grass-dev@…,"taken from the dev ML [1]: {{{ >>Like this you check if the difference is very small and below the >>acceptable threshold. >>In C, we use GRASS_EPSILON for these comparisons. > > now done with GRASS_EPSILON 1.0e-15 > > r.mapcalc expression=difftestepsilon = if( abs( accum32bit at accumtest - > accum64bit at accumtest) <= 1.0e-15, 1 , 100 ) > > attached a screenshot of this map > > accum_diff_wingrass32bitvs64bit.png > Mhh.. Can you open a ticket with all relevant bits + the difference screenshot along with a legend and ""r.univar -e"" output? }}} tested with the NC sample data set on the same 64bit- win7 box running 32bit and 64bit winGRASS binaries. {{{ GRASS version: 7.0.3RC1 GRASS SVN Revision: 67443 Build Date: 2015-12-31 Build Platform: i386-w64-mingw32 GDAL/OGR: 1.11.3 PROJ.4: 4.9.2 GEOS: 3.5.0 SQLite: 3.7.17 Python: 2.7.4 wxPython: 2.8.12.1 Platform: Windows-7-6.1.7601-SP1 (OSGeo4W) g.region -p -a raster=elevation@PERMANENT align=elevation@PERMANENT projection: 99 (Lambert Conformal Conic) zone: 0 datum: nad83 ellipsoid: a=6378137 es=0.006694380022900787 north: 228500 south: 215000 west: 630000 east: 645000 nsres: 10 ewres: 10 rows: 1350 cols: 1500 cells: 2025000 r.watershed elevation=elevation@PERMANENT accumulation=accum_wg32bit SECTION 1a (of 4): Initiating Memory. SECTION 1b (of 4): Determining Offmap Flow. SECTION 2: A* Search. SECTION 3a: Accumulating Surface Flow with MFD. SECTION 3b: Adjusting drainage directions. SECTION 4: Closing Maps. (Thu Jan 07 11:30:02 2016) Command finished (40 sec) r.univar -e map=accum_wg32bit@watershedtest total null and non-null cells: 2025000 total null cells: 0 Of the non-null cells: ---------------------- n: 2025000 minimum: -638533 maximum: 330838 range: 969371 mean: -262.231 mean of absolute values: 685.177 standard deviation: 13021.3 variance: 1.69554e+008 variation coefficient: -4965.58 % sum: -531016814.625176 1st quartile: 2.03496 median (even number of cells): 4.11548 3rd quartile: 9.49 90th percentile: 34.8313 (Thu Jan 07 11:31:41 2016) Command finished (17 sec) }}} {{{ System Info GRASS version: 7.0.3RC1 GRASS SVN Revision: 67443 Build Date: 2015-12-31 Build Platform: x86_64-w64-mingw32 GDAL/OGR: 1.11.3 PROJ.4: 4.9.2 GEOS: 3.5.0 SQLite: 3.7.17 Python: 2.7.5 wxPython: 2.8.12.1 Platform: Windows-7-6.1.7601-SP1 (OSGeo4W) g.region -p projection: 99 (Lambert Conformal Conic) zone: 0 datum: nad83 ellipsoid: a=6378137 es=0.006694380022900787 north: 228500 south: 215000 west: 630000 east: 645000 nsres: 10 ewres: 10 rows: 1350 cols: 1500 cells: 2025000 r.watershed elevation=elevation@PERMANENT accumulation=accum_wg64bit SECTION 1a (of 4): Initiating Memory. SECTION 1b (of 4): Determining Offmap Flow. SECTION 2: A* Search. SECTION 3a: Accumulating Surface Flow with MFD. SECTION 3b: Adjusting drainage directions. SECTION 4: Closing Maps. (Thu Jan 07 11:38:49 2016) Command finished (4 sec) r.univar -e map=accum_wg64bit@watershedtest total null and non-null cells: 2025000 total null cells: 0 Of the non-null cells: ---------------------- n: 2025000 minimum: -638533 maximum: 330838 range: 969371 mean: -262.231 mean of absolute values: 685.177 standard deviation: 13021.3 variance: 1.69554e+008 variation coefficient: -4965.58 % sum: -531016814.625176 1st quartile: 2.03496 median (even number of cells): 4.11548 3rd quartile: 9.49 90th percentile: 34.8313 (Thu Jan 07 11:39:36 2016) Command finished (6 sec) }}} {{{ r.mapcalc expression=difftestepsilon = if( abs( accum_wg32bit@watershedtest - accum_wg64bit@watershedtest ) <= 1.0e-15 , 1 ,100 ) }}} {{{ r.univar -e map=difftestepsilon@watershedtest total null and non-null cells: 2025000 total null cells: 0 Of the non-null cells: ---------------------- n: 2025000 minimum: 1 maximum: 100 range: 99 mean: 32.5001 mean of absolute values: 32.5001 standard deviation: 46.1113 variance: 2126.25 variation coefficient: 141.881 % sum: 65812680 1st quartile: 1 median (even number of cells): 1 3rd quartile: 100 90th percentile: 100 }}} [1] https://lists.osgeo.org/pipermail/grass-dev/2016-January/078282.html ",defect,closed,normal,7.0.5,Raster,svn-releasebranch70,worksforme,,,x86-64,MSWindows 7