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 Note that the archive is no longer being updated. We provide the archive for reference; many of the answers presented here remain technically correct, even if somewhat outdated.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.
> By spatial subset, do you mean the subsetting like plotting every > other vector, or do you mean subsetting like restricting the region to > a specified bounding box? > I mean do not restrict to a bounding box, if you did spatial subset in the IDV (by bounding box or match display region), the result would be good. Yuan > On Tue, Jul 7, 2015 at 11:33 AM, Unidata IDV Support > <address@hidden> wrote: > >> Rich, > >> > >> When I create my own bundle for these data, I see essentially no > >> difference between IDV and Python. See attached bundle and images. > >> > >> Best, > >> > >> Unidata IDV Support > >> > > > > Rich, > > > > Somehow I noticed that the results in the IDV were different with and > > without the spatial subset, even if the spatial subset covers the whole > > dataset. > > Would you be able to verify this in the Python? > > > > > > > > Yuan > >> > >> > > Yuan, > >> > > So when you run my bundle, do you get the same result? > >> > > -Rich > >> > > > >> > > >> > When I ran the bundle, I got even worst result. My feeling is that those > >> > missing vectors were likely associated with very small values. If you > >> > draw wind barb, you will get every points. > >> > > >> > > >> > Yuan > >> > > On Thu, Jul 2, 2015 at 11:54 AM, Unidata IDV Support > >> > > <address@hidden> wrote: > >> > > >> We are running 5.1u2. Did you look at the bundle? All your > >> > > >> questions are answered by the bundle, no? > >> > > > > >> > > > > >> > > > Rich, > >> > > > I have no problem getting the result similar to the python > >> > > > output. See the attached. However, your bundle does look very > >> > > > strange, almost like some kind of > >> > > > filter working there. I will check and let you know. > >> > > > > >> > > > > >> > > > Yuan > >> > > >> > >> > > >> On Wed, Jul 1, 2015 at 5:34 PM, Unidata IDV Support > >> > > >> <address@hidden> wrote: > >> > > >> > Rich, > >> > > >> > > >> > > >> > Here are a few comments: > >> > > >> > > >> > > >> > - Update your IDV to the latest version (5.1u2, this will yield > >> > > >> > no improvement > >> > > >> > probably, but it is usually best to work with the latest version > >> > > >> > of the IDV). > >> > > >> > > >> > > >> > - For clarification, the flow vectors are supposed to be derived > >> > > >> > from what? The > >> > > >> > data contain two u and v fields (momentum versus stokes). Which > >> > > >> > one are you > >> > > >> > interested in? (I wonder if there is confusion/mismatches going > >> > > >> > on here.) > >> > > >> > > >> > > >> > - Are you sure you are looking at the same geographic extents? > >> > > >> > The IDV is > >> > > >> > displayed roughly over NY harbor. I cannot tell where the Python > >> > > >> > plot is > >> > > >> > located. > >> > > >> > > >> > > >> > - I wonder if there are numerical errors going on. One of the > >> > > >> > Derived Fields in > >> > > >> > the IDV is "Speed (from U & V)". When you do a "Value Plot" of > >> > > >> > these data, do > >> > > >> > you get numbers you expect? > >> > > >> > > >> > > >> > - Experiment with the Flow Vector Control in the IDV Dashboard, > >> > > >> > Displays Tab. > >> > > >> > > >> > > >> > Keep us up-to-date on your progress. > >> > > >> > > >> > > >> > Best, > >> > > >> > > >> > > >> > Unidata IDV Support > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> > > >> >> IDV Gurus, > >> > > >> >> > >> > > >> >> We are struggling to get bottom velocity vectors displayed > >> > > >> >> properly in > >> > > >> >> IDV (5.0u2) for a Hurricane Sandy ocean simulation. > >> > > >> >> > >> > > >> >> The bottom velocity for 2012-10-30 00:00:00 should look like the > >> > > >> >> 1st > >> > > >> >> attached image (plotted in python using this notebook): > >> > > >> >> http://nbviewer.ipython.org/gist/rsignell-usgs/a85e68a71933910a171a > >> > > >> >> > >> > > >> >> but instead it looks like the 2nd attached image. > >> > > >> >> > >> > > >> >> In the IDV image you can see that the flow at the coast is the > >> > > >> >> wrong > >> > > >> >> direction, and there are those strange black areas with no > >> > > >> >> vectors. > >> > > >> >> > >> > > >> >> What is going on here? > >> > > >> >> > >> > > >> >> I'm attaching the bundle so you can recreate this yourself. > >> > > >> >> -- > >> > > >> >> Dr. Richard P. Signell (508) 457-2229 > >> > > >> >> USGS, 384 Woods Hole Rd. > >> > > >> >> Woods Hole, MA 02543-1598 > >> > > >> >> > >> > > >> >> > >> > > >> > > >> > > >> > > >> > > >> > Ticket Details > >> > > >> > =================== > >> > > >> > Ticket ID: WHS-790529 > >> > > >> > 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: WHS-790529 > >> > > > Department: Support IDV > >> > > > Priority: Normal > >> > > > Status: Open > >> > > > >> > > > >> > > > >> > > -- > >> > > Dr. Richard P. Signell (508) 457-2229 > >> > > USGS, 384 Woods Hole Rd. > >> > > Woods Hole, MA 02543-1598 > >> > > > >> > > > >> > > > > > > Ticket Details > > =================== > > Ticket ID: WHS-790529 > > 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: WHS-790529 Department: Support IDV Priority: Normal Status: Open