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[GEMPAK #SBY-446537]: gfunc equations error within gddiag

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  • Subject: [GEMPAK #SBY-446537]: gfunc equations error within gddiag
  • Date: Fri, 09 Sep 2011 18:10:02 -0600
Lines 149 and 161 of your script need to reference the second GDFILE defintion 
with a '+2':

148: gdfile = ${grid} + turbc.grd
149: 
gfunc=mul(log(quo(evap+2,6.112)),quo(243.5,(sub(17.67,log(quo(evap+2,6.112))))))

160: gdfile = ${grid} + turbc.grd
161: gfunc=quo(mul(237.7,gamma+2),sub(17.271,gamma+2))

make these edits and it should run without error.

Michael



> I have several gridded functions that I cannot seem to get working while 
> using a combination of gdcfil and gddiag.
> 
> I am using the 1.0 degree GFS as my grid file.
> 
> 
> 
> Attached is my C-shell script.
> 
> 
> 
> Please note that I am having problems only with calculating and using the 
> custom grid parms: tdp@1000, evap, gamma, and tdp2.
> 
> 
> 
> gfunc=add(1.001,mul(.0034,quo(sub(pres,100.0),900.0))
> 
> grdnam=evap
> 
> r
> 
> 
> 
> gdfile = ${grid} + turbc.grd
> 
> gfunc=mul(log(quo(evap,6.112)),quo(243.5,(sub(17.67,log(quo(evap,6.112))))))
> 
> grdnam=tdp@1000
> 
> r
> 
> 
> 
> gdfile = ${grid}
> 
> gfunc=add(quo(mul(17.271,tmpc),add(237.7,tmpc)),log(quo(relh,100)))
> 
> grdnam=gamma@1000
> 
> r
> 
> 
> 
> gdfile = ${grid} + turbc.grd
> 
> gfunc=quo(mul(237.7,gamma),sub(17.271,gamma))
> 
> grdnam=tdwp2@1000
> 
> r
> 
> The evap and tdp are equations from 
> /usr/nawips/GEMPAK/source/diaglib/pd/pddwpt.c:
> 
> ratio = rmix [i];
> 
> if ( ratio > .05F ) ratio /= 1000.0F;
> 
> 
> 
> /*
> 
> * Calculate vapor pressure from mixing ratio and pressure.
> 
> */
> 
> e = ( pres [i] * ratio ) / ( .62197F + ratio );
> 
> 
> 
> /*
> 
> * Correct vapor pressure.
> 
> */
> 
> e /= ( 1.001F + ((pres [i] - 100.0F) / 900.0F) * .0034F );
> 
> 
> 
> /*
> 
> * Calculate dewpoint.
> 
> */
> 
> dwpc [i] = log (e/6.112F) * 243.5F / (17.67F - log (e/6.112F));
> 
> 
> 
> Gamma is calculated using the equation below; where a=17.271 and b=237.7 °C
> 
> 
> 
> 
> 
> Tdp2 is calculated using the result of gamma:
> 
> 
> 
> 
> 
> After running my script, I am getting these errors within gddiag:
> 
> GEMPAK-GDDIAG> [DG -7]  Input grid EVAP ^110907/1200F006 @1000 %PRES in QUO 
> cannot be found.
> 
> GEMPAK-GDDIAG> [DG -7]  Input grid EVAP ^110907/1200F006 @1000 %PRES in QUO 
> cannot be found.
> 
> 
> 
> I am gridding these individually because I want to run gdinfo or gdpoint to 
> lookup a value for each grdnam.
> 
> 
> 
> Any help would be greatly appreciated.
> 
> 
> 
> Thanks.
> 
> 
> 
> Andrew Little
> 
> Weather Systems Analyst
> 
> Universal Weather & Aviation
> 
> 8787 Tallyho Road
> 
> Houston, Texas 77061
> 
> (713) 947-5633
> 
> (713) 504-2719
> 
> 
> 
> address@hidden
> 
> 
> 
> Success from the word GO.
> 
> 
> 


Ticket Details
===================
Ticket ID: SBY-446537
Department: Support GEMPAK
Priority: Normal
Status: Open