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[IDV #NJK-709837]: IDV function for land/sea topo scaling

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  • Subject: [IDV #NJK-709837]: IDV function for land/sea topo scaling
  • Date: Fri, 05 Mar 2010 15:06:30 -0700
Rich-

> What I want is:
> 
> a=a/10   (a>0)
> a=a       (a<=0)

Define a Jython procedure:

def scaleGrid(grid):
    p = grid.clone()
    for i in range(len(p)):
      a = p[i]
      if a > 0: 
        p[i]=a/10
    return p

You could modify that to pass in a scale and threshold and provide defaults:

def scaleGrid(grid, thresh=0, scale=10):
    p = grid.clone()
    t = int(thresh)
    s = int(scale)
    for i in range(len(p)):
      a = p[i]
      if a > t: 
        p[i]=a/s
    return p

Don
> On Fri, Mar 5, 2010 at 4:54 PM, Unidata IDV Support
> <address@hidden> wrote:
> >> Jeff,
> >> I seem to remember you saying to pass new function ideas along, so here 
> >> goes...
> >>
> >> I often want to load in DEM data (land topo/sea bathy) for visualizing
> >> along with ocean modeling applications in IDV, but I want to provide a
> >> different vertical exaggeration for the land and ocean topography,
> >> because I want to clearly show the coastal ocean topography, but
> >> without the land topography looking like skyscrapers.   For example,
> >> I'd like to scale the depths below 0 by a different factor than the
> >> elevations above 0.    I imagine this is pretty simple, but still
> >> don't know how.
> >>
> >
> > Hi Rich,
> > Just make a formula called scale, e.g., to scale by 2:
> >
> >     fieldYouWantToScale*2
> >
> > That should work.
> >
> > -Jeff
> >
> >
> >
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: NJK-709837
> > Department: Support IDV
> > Priority: Normal
> > Status: Closed
> >
> >
> 
> 
> 
> --
> Dr. Richard P. Signell   (508) 457-2229
> USGS, 384 Woods Hole Rd.
> Woods Hole, MA 02543-1598
> 
> 


Ticket Details
===================
Ticket ID: NJK-709837
Department: Support IDV
Priority: Normal
Status: Open