Your problem in precision of the stored diagnostic is due to your GPACK
setting in GDDIAG.
The GPACK parameter will use GRIB/16 if left blank. Since you identified
the problem as a large range of data values, you likely need to increase
the number of packing bits being used, or set GPACK=NONE.
Unidata User Support
On Tue, 2006-06-27 at 13:59, Melick, Christopher James (UMC-Student)
I am having problems with the output generated within GDDIAG when I am declaring a parameter in GRDNAM that is the quotient of two parameters, the one in the denominator encompassing a large range in scales [in this instance, the squared difference of the vertical change in geostrophic wind]. Several grid points will have identical values if I use the newly generated grid file which should not occur. However, a completely different and more accurate result will occur if I manually type in the quotient of the two parameters myself in GFUNC. What causes this and is there a means to fix it?? I hope I have explained my dilemma clearly and completely enough to follow. There are no GEMPAK errors in the logfiles and I have tried creating a separate script just for this particular term with no success.
Thank you very much,
Christopher J. Melick
Ph.D. Student, Atmospheric Science
Department of Soil, Env, and Atmos Sciences
University of Missouri-Columbia
302 ABNR Building
Columbia, MO 65211