Re: [gembud] GEMPAK Script Question

Thanks for the replies...but that raises a bigger question concerning the
execution of the formula. For example, the 'quo(urel,mag(vecr(urel,0)))'
portion. As I understand it, working from 'inside-out',
vecr(urel,0)  will result in V1 = urel & V2 = 0 for each grid point. Then,
the mag(V1,V2) will always be the value of V1 ( SQRT(V1*V1) + (V2*V2) )
since 0*0=0 & the square root of V1*V1 is...V1. Next, 'quo(urel,V1)' will
always yield 1 since v1 still equals urel. What is the purpose of jumping
through all those hoops if the answer is always "1"...or am I missing
something?

BTW - this is from some NCEP post processing routine to calculate slantwise
CAPE. This portion calculates 'alpha' where the in-line comment states:
"alpha...with u and v can use alpha to get momentum as needed."

Thanks again,
Jeff

On Tue, Feb 11, 2020 at 11:22 AM Steve Decker <sgdecker@xxxxxxxxxxxxxxxxxx>
wrote:

> Jeff,
>
> That would be my interpretation.  It's essentially constructing the zonal
> wind (actually the left-to-right wind on the grid since urel is used) as a
> vector.
>
> Cheers,
> Steve
>
> On 2/11/20 10:57 AM, Jeffrey Krob - NOAA Federal via gembud wrote:
>
> All,
>
> GEMPAK 'newbie' here - came across a script which is passed to the
> DG_GRIDN routine as the following:
>
> custar =
> 'mul(acos(quo(mul(mag(vasv(vecr(urel,0),geo)),quo(urel,mag(vecr(urel,0)))),urel)),RTD)'
>
> Question; concerning the 'vecr(urel,0)' portion, I understand this is a
> call to the DV_VECR (S1, S2) routine to create a vector from 2 scalars.
> However, with the second argument being a '0', is this only returning the
> 'U' portion of the U/V wind vector or is something else going on here?
>
> Thanks in advance,
> Jeff Krob
> NOAA/NESDIS
>
> _______________________________________________
> NOTE: All exchanges posted to Unidata maintained email lists are
> recorded in the Unidata inquiry tracking system and made publicly
> available through the web.  Users who post to any of the lists we
> maintain are reminded to remove any personal information that they
> do not want to be made public.
>
>
> gembud mailing listgembud@xxxxxxxxxxxxxxxx
> For list information or to unsubscribe,  visit: 
> https://nam02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.unidata.ucar.edu%2Fmailing_lists%2F&amp;data=02%7C01%7Csgdecker%40envsci.rutgers.edu%7C244cffa4bf69475b855908d7af0b287c%7Cb92d2b234d35447093ff69aca6632ffe%7C1%7C0%7C637170334775505732&amp;sdata=K5apE8mmd8Mz9uqNixzHzJYMRO5qyYUO%2F0SHQifmF9Q%3D&amp;reserved=0
>
>
> --
> Steve Decker, Associate Teaching Professor
> Director, Meteorology Undergraduate Program
> Department of Environmental Sciences           Phone: (848) 932-5750
> Rutgers University                               Fax: (732) 932-8644
> 14 College Farm Rd                  Email: decker@xxxxxxxxxxxxxxxxxx
> New Brunswick, NJ  08901-8551
>
>
  • 2020 messages navigation, sorted by:
    1. Thread
    2. Subject
    3. Author
    4. Date
    5. ↑ Table Of Contents
  • Search the gembud archives: