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>From: Owen Cooper <address@hidden> >Organization: NOAA Aeronomy Laboratory, R/AL4 >Keywords: 200110152028.f9FKS0123855 McIDAS GRDDISP Owen, >Okay, how do I get around this one? > >I have a batch that plots AVN realtime grids every six hours, fired off by >a cron job. >The AVN data have several projections: >a full northern hemisphere polar stereographic >2 polar stereographic versions of N. AMerica >1 Mercator of the the entire planet > >If I use the command: >GRDDISP RTGRIDS/AVN DAY=#Y TIME=0 PARAM=P LEV=MSL FHOUR=0 > >It will grab the first GRID that fits this decription and plot it up. Right. >This is usually the northern hemi. polar-stereographic, the one that I >want. This is not, however, guaranteed. >But often the first grid that fits this description is one of the >North American plots, which does me no good as I want to see what's going >on over Europe. Is there any way to tell MCIDAS which specific projection >I want? Yes. Use the GPRO= keyword for GRDDISP. For instance, the following will always get you the LAMBert Conformal grid: GRDDISP RTGRIDS/AVN DAY=#Y TIME=0 PARAM=P LEV=MSL FHOUR=0 GPRO=LAMB >It doesn't look like specifying the grid number will do any good >seeing as the grid numbers change in addition to the order in which the >projections are available. Right. In order to use the grid number, you would have to do a GRDLIST to find out the grid numbers first (ugly). Using the GPRO= keyword will get you around this, but it wouldn't get you around the case where you have more than one Lambert Conformal grid of P at MSL for the same DAY and TIME you are interested in. For that case, you would have to do a list and then use the grid number. >Any suggestions? Let me know if you run into amy problems using GPRO=. >Thanks >Owen > >Owen Cooper >National Research Council Associate >NOAA Aeronomy Laboratory, R/AL4 >325 Broadway >Boulder CO 80305 >ph: (303) 497-3599 >fax: (303) 497-5686 Tom