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Ok, Yeah, I think it is a gaussian grid, thanks for the info. Pete In a previous message to me, you wrote: > >Pete, > >If I read your wgrib output correctly, >the GDS type 4 is a gaussian grid which GEMPAK does not >handle regardless of number of points since the GEMPAK >grid library uses regularly spaced rows. > >When dealing with larger grids in general, you can define LLMXTG >to the size of the input grid, while using LLMXGD as the largest >subset of the LLMXTG for viewing and using the IJSKIP parameter. > >The ndfd decoder does support a GSKIP parameter for subsampling >the input grib2 data, which is something I'll try to >support in dcgrib2 in the future, but since you seem to >have gaussian grids, that isn't going to solve your problem here. > >Steve Chiswell >Unidata User Support > > >>From: address@hidden (Pete Pokrandt) >>Organization: UCAR/Unidata >>Keywords: 200412141831.iBEIVXlI009124 > >>-------- >> >>Steve, >> >>A user of ours has some ECMWF grib files from an archive that he >>cannot decode. The problem appears to be that the input grid >>is too large. Is there any way to increase the dimensions, or >>to have dcgrib2 decode only over a limited domain? >> >>The command used to convert was: >> >>cat mrz02_142_143.grb | /home/gempak/GEMPAK5.7.2p2/bin/linux/dcgrib2 -d ./te >st >> .log -e GEMTBL=/home/gempak/GEMPAK5.7.2p2/gempak/tables mrz02_142_143.gem >> >>The error message I get is: >>[14912] 041214/1128 [DCGRIB -55] Grid too large 65535 x 512 [33553920 > 7500 >00 >> ] >> >>The grib file appears to be a 1/3 degree global grid, thinned in the x direc >ti >> on, so there are 512 points from SP to NP, and 1024 around the equator, wit >h >>fewer in the x direction as you move away from the equator. >> >>From grads 'wgrib', I have the following info: >> >>rec 1:0:date 2002010400 LSP kpds5=142 kpds6=1 kpds7=0 levels=(0,0) grid=255 >sf >> c ECMWF stream? 24hr fcst: >> LSP=Large scale precipitation m >> timerange 0 P1 24 P2 0 TimeU 1 nx -1 ny 512 GDS grid 4 num_in_ave 0 missi >ng >> 0 >> center 98 subcenter 0 process 199 Table 128 >> thinned gaussian: lat 89.731000 to -89.731000 >> lon 0.000000 348528 grid pts (-1 x 512) scan 0 mode 0 bdsgrid 1 nl >at >> : >> 18 25 32 40 45 50 60 64 72 72 75 81 90 96 1 >00 >> 108 120 120 125 135 144 150 160 160 180 180 180 192 192 2 >00 >> 216 216 216 225 240 240 243 250 256 270 270 288 288 288 3 >00 >> 300 320 320 320 324 360 360 360 360 360 360 375 375 384 3 >84 >> 400 400 400 432 432 432 432 432 450 450 450 480 480 480 4 >80 >> 480 486 500 500 500 512 512 540 540 540 540 540 576 576 5 >76 >> 576 576 576 600 600 600 600 600 640 640 640 640 640 640 6 >40 >> 640 648 675 675 675 675 675 675 720 720 720 720 720 720 7 >20 >> 720 720 729 729 750 750 750 750 750 768 768 768 768 800 8 >00 >> 800 800 800 800 800 800 810 810 864 864 864 864 864 864 8 >64 >> 864 864 864 864 864 864 864 900 900 900 900 900 900 900 9 >00 >> 900 900 900 960 960 960 960 960 960 960 960 960 960 960 9 >60 >> 960 960 960 960 960 960 960 960 960 960 972 972 972 972 9 >72 >> 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 10 >00 >> 1000 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 10 >24 >> 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 10 >24 >> 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 10 >24 >> 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 10 >24 >> 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 10 >24 >> 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 1024 10 >24 >> 1024 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 1000 10 >00 >> 1000 1000 972 972 972 972 972 960 960 960 960 960 960 960 9 >60 >> 960 960 960 960 960 960 960 960 960 960 960 960 960 960 9 >00 >> 900 900 900 900 900 900 900 900 900 900 864 864 864 864 8 >64 >> 864 864 864 864 864 864 864 864 864 810 810 800 800 800 8 >00 >> 800 800 800 800 768 768 768 768 750 750 750 750 750 729 7 >29 >> 720 720 720 720 720 720 720 720 720 675 675 675 675 675 6 >75 >> 648 640 640 640 640 640 640 640 640 600 600 600 600 600 5 >76 >> 576 576 576 576 576 540 540 540 540 540 512 512 500 500 5 >00 >> 486 480 480 480 480 480 450 450 450 432 432 432 432 432 4 >00 >> 400 400 384 384 375 375 360 360 360 360 360 360 324 320 3 >20 >> 320 300 300 288 288 288 270 270 256 250 243 240 240 225 2 >16 >> 216 216 200 192 192 180 180 180 160 160 150 144 135 125 1 >20 >> 120 108 100 96 90 81 75 72 72 64 60 50 45 40 >32 >> 25 18 >> min/max data -2.6846e-17 0.302269 num bits 16 BDS_Ref -2.6846e-17 DecSc >al >> e 0 BinScale -17 >> >>You can grab the input grib file for testing if that helps, from >>http://sysadm.aos.wisc.edu/~poker/jan02_142_143.grb >> >>Thanks for any info or advice! >> >>Pete >>-- >>+>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>+<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<+ >>^ Pete Pokrandt V 1447 AOSS Bldg 1225 W Dayton St^ >>^ Systems Programmer V Madison, WI 53706 ^ >>^ V address@hidden ^ >>^ Dept of Atmos & Oceanic Sciences V (608) 262-3086 (Phone/voicemail) ^ >>^ University of Wisconsin-Madison V 262-0166 (Fax) ^ >>+<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<+>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>+ >> >-- >**************************************************************************** >< >Unidata User Support UCAR Unidata Program >< >(303)497-8643 P.O. Box 3000 >< >address@hidden Boulder, CO 80307 >< >---------------------------------------------------------------------------- >< >Unidata WWW Service http://my.unidata.ucar.edu/content/support >< >---------------------------------------------------------------------------- >< >NOTE: All email exchanges with Unidata User Support are recorded in the >Unidata inquiry tracking system and then made publicly available >through the web. If you do not want to have your interactions made >available in this way, you must let us know in each email you send to us. -- +>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>+<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<+ ^ Pete Pokrandt V 1447 AOSS Bldg 1225 W Dayton St^ ^ Systems Programmer V Madison, WI 53706 ^ ^ V address@hidden ^ ^ Dept of Atmos & Oceanic Sciences V (608) 262-3086 (Phone/voicemail) ^ ^ University of Wisconsin-Madison V 262-0166 (Fax) ^ <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<+>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>+