Hi Tyn-
Valentijn Venus wrote:
Can the same be used on for gradient in 3 dimensions ?
No, it's just the horizontal gradient:
GRAD ( S ) = [ DDX ( S ), DDY ( S ) ]
Don
-----Original Message-----
From: idvusers-bounces@xxxxxxxxxxxxxxxx
[mailto:idvusers-bounces@xxxxxxxxxxxxxxxx] On Behalf Of Don Murray
Sent: Friday, May 01, 2009 9:06 PM
To: Stuart Wier
Cc: IDV Users
Subject: Re: [idvusers] IDV formula for gradient of scalar field
Hi Stu-
Stuart Wier wrote:
I need to make an IDV formula to make the gradient of a 2d scalar
field (a new 2d vector field), and also the magnitude of the gradient
as a new scalar field. Anyone know how to do that offhand?
You can use the grad(S) python procedure in the griddiag.py module to
compute the gradient. Use the mag(V) procedure to compute the magnitude
of the resulting vector:
mag(grad(S))
You can use the Grid->Define a grid diagnostic Formula to try this on
the fly, or create a formula.
All the jython procedures are documented at:
http://www.unidata.ucar.edu/software/idv/docs/userguide/tools/JythonLib.
html
(I just noticed that the mag function on that page is not formatted
correctly. I'll fix that for a future release).
Don
*************************************************************
Don Murray UCAR Unidata Program
dmurray@xxxxxxxxxxxxxxxx P.O. Box 3000
(303) 497-8628 Boulder, CO 80307
http://www.unidata.ucar.edu/staff/donm
*************************************************************
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*************************************************************
Don Murray UCAR Unidata Program
dmurray@xxxxxxxxxxxxxxxx P.O. Box 3000
(303) 497-8628 Boulder, CO 80307
http://www.unidata.ucar.edu/staff/donm
*************************************************************
