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>From: "Mekonnen Gebremichael" <address@hidden> >Organization: Pratt School of Engineering, Duke University >Keywords: 200504201601.j3KG1gv2005753 McIDAS probing image values Hi Mekonnen, Sorry for the silence, I have been working on the next McIDAS distribution. >I obtained GOES-8 IR data (single band) from UW SSEC (this site has 30-min >GOES IR data, so I decided to make use of these data). Sounds good. >I copied the original data corresponding to Julian day 183 to >'/disk/space/mek11/USdata/GOESssec/183/. >I did dsserve.k (I created a dataset named 183IR/AREA). After I did >imglist.k, this was what I found: > >Image file directory listing for:183IR/AREA > Pos Satellite/ Date Time Center Res (km) >Image_Size > sensor Lat Lon Lat Lon > --- ------------- ------------ -------- ---- ---- ----- ----- >------------ > 47 G-8 IMG 2 JUL 02183 23:45:00 37 94 > Band: 4 10.7 um IR Surface/Cloud-top Temp 5.89 2.61 410 x >1832 > proj: 0 created: 2005172 172642 memo: RT GVAR > type:GVAR cal type:RAW > offsets: data= 3328 navigation= 256 calibration= 2816 auxiliary= >0 > doc length: 228 cal length: 0 lev length: 0 PREFIX= 232 > valcod: 183234500 zcor: 0 avg-smp: N > start yyddd: 2002183 start time:234513 start scan: 323 > lcor: 3593 ecor: 8861 bytes per pixel: 2 ss: 70 > Resolution Factors (base=1): Line= 4.0 Element= 4.0 >imglist.k: done OK, I just logged onto sagres and see the dataset. >Then I did imgcopy and axform, for two different datasets. The resulting >ascii files (with UNIT=TEMP) are 'testout1' and 'testout40', which are >available at '/disk/space/mek11/mcidas/data/'. The lower portion of both >datasets are 0, the LAT/LON values over some grids are -1.0. >Could you please help me figure out what went wrong? FYI, I think that the "problem" you are seeing is related to how you did the IMGCOPY. Here is a repeat of the script you said you were intending on using: #!/bin/ksh #===================================================== # THESE ENV. VAR. ARE COPIED from TOM with slight modification #===================================================== SHELL=bin/ksh export SHELL # # First, define MCHOME as the HOME directory for the user under which # McIDAS-X is installed. # MCHOME=/home/mcidas MCDATA=$HOME/mcidas/data # Set MCPATH using MCDATA and MCHOME MCPATH=${MCDATA}:$MCHOME/data:$MCHOME/help # Define MCLOG to be $MCDATA/mcbatch.log MCLOG=$MCDATA/mcbatch.log # Setup PATH so that the McIDAS-X executables can be found PATH=$MCHOME/bin:$PATH # Set LD_LIBRARY_PATH to include all directories (other than those >searched # by default) that are needed to be searched to find shared libraries. LD_LIBRARY_PATH=$MCHOME/lib:$LD_LIBRARY_PATH if [ -f "${MCDATA}/MCTABLE.TXT" ]; then MCTABLE_READ="${MCDATA}/MCTABLE.TXT;${MCHOME}/data/ADDESITE.TXT" else MCTABLE_READ="${MCHOME}/data/ADDESITE.TXT" fi export MCHOME MCDATA MCLOG MCPATH PATH MCTABLE_READ LD_LIBRARY_PATH cd $MCDATA #============================================================ # PROCESSING THE DATA FILES #============================================================ home0=/disk/space/mek11/USdata/GOES cd $home0 data=$(ls A*) y=1 for file in $data do imgcopy.k TEST1/AREA.$y MYDATA/IMAGES.3000 axform.k 3000 testout$y FTYPE=ASC NAV=YES UNIT=TEMP let y=y+1 done I now note that in this script you are using the default location and size in the IMGCOPY of the original image to the output sector, MYDATA/IMAGES.3000 (AREA3000). The default location is the upper left hand corner of the image; the default size is 480 lines and 640 elements. Please see the online help for IMGCOPY for more information: HELP IMGCOPY If you display any of the images, you will see that the upper left hand corner is off in space. Here is one example: original image: http://www.unidata.ucar.edu/content/staff/tom/gifs/mek11_orig.gif sector created with 'IMGCOPY 183IR/AREA MYDATA/IMAGES.3000': http://www.unidata.ucar.edu/content/staff/tom/gifs/mek11_sector.gif The dump of values from the sector using: AXFORM 3000 testout1 FTYPE=ASC NAV=YES UNIT=TEMP will try to give a data value and Lat,Lon for each pixel in the sector. The data values and earth locations for pixels in space are undetermined so AXFORM will write out a missing value ('-1' for Lats/Lons). I think that you forgot to include the center location for the copy in the IMGCOPY command. NB: even if you do include the center point and and sector output size, you can still create a sector that has portions either in space (e.g., the upper left hand corner of the images you are using in 183IR/AREA), or where there are not data values (e.g., if your sector box extends outside of the region where the sector has data values, line on the right hand or lower sides of the sector). You must choose a sector that is totally within the earth-location of the image or decide how you are going to deal with the missing data values you are getting in your 'testout' files. >when I downloaded >these data (for julian days ranging from 182 to 189), I also received files >such as imglist.txt (available at '/disk/space/mek11/USdata/GOESssec/mek), >though I do not know if they are helpful at all. The image has all of the information you need, so the .txt files are not of much use. >Thanks much, No worries. Please let me know if the above is not clear. Cheers, Tom -- 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.