This archive contains answers to questions sent to Unidata support through mid-2025. Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated. For the most up-to-date information on the use of NSF Unidata software and data services, please consult the Software Documentation first.
Mike, I have been able to duplicate your problem. I suspect that the rewrite of some of the old Fortran routines to C is simply missing one of the rules for converting SPFH. I'll work on this and let you know when Its fixed. In the mean time, you have a workaround that suits your needs it sounds like. Steve Chiswell Unidata User Support On Tue, 2007-02-06 at 06:49 -0600, Mike Bender wrote: > Steve, > > No joy using RELH(tmpc,dwpc). Gdvint indicates it is using RELH from > the PRES grids to compute the THTA surfaces. A gdinfo shows SPFH (which > I think is specific humidity) is output to THTA interpolation (which has > always been in the past looking at older saved model data). I am > getting by by using an older version of gdplot and renaming it to > gdplot_isent just to get the RH to output. I have not had to mess with > GDVINT in over 15 years (Ron Miller showed me how to use it for isent > computations), so this is the first time I have ever really had > problems, lucky me I guess. I will keep digging into this as time > allows, but for now, my work around works! > > Mike > > > > Steve Chiswell wrote: > > Mike, > > > > Have you tried using the RELH(tmpc,dwpc) function? What grids are > > available on your 292K THTA coordinate? > > > > Steve Chiswell > > Unidata User Support > > > > > > On Mon, 2007-02-05 at 07:17 -0600, Mike Bender wrote: > >> Steve, > >> > >> I have noticed with gempak594 that there is a problem using relh in thta > >> coords. I have been gdplot_nc in the past to generate say the 292K > >> surface of pressure, wind, and relh. However now it says it can't find > >> "RELH" on the requested grids. Gdvint worked fine on the NAM and I > >> doubled checked it this morning. This error is occurring on RHEL4 EMT64 > >> machines and FEDORA CORE 6 32 bit machines. > >> > >> I went back and used the previous version of GEMPAK's gdplot program on > >> last nights NAM run, and I got RELH to output just fine. > >> > >> Oh, one other note, the RHEL4 EMT64 machines had GEMPAK594 compiled into > >> them, while the FC6 machines had the pre-compiled binaries loaded in. > >> What is very strange is, you can output MIXR! but no RELH. > >> > >> Thanks > >> Mike Bender > >> Senior Meteorologist/ITO > >> MMAC, Oklahoma City, OK > >> -- Steve Chiswell <address@hidden> Unidata