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[IDV #ABK-864576]: Trajectory Bug

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  • Subject: [IDV #ABK-864576]: Trajectory Bug
  • Date: Mon, 02 Jun 2014 11:21:57 -0600
> Yuan:
> 
> I'm using RAP grids (13-km) obtained from NCDC and housed on our local
> disk system.  Thus, you won't be able to access them unless I output a
> zidv file.
> 
> I'm curious if you use separate codes for the 2D and 3D trajectories?
> Using the nightly build downloaded this morning with your corrections, I
> generated 2D and 3D trajectories and there still seems to be a problem
> with the 2D trajectories (these are backwards trajectories as before and
> the wind vectors are for the "last" time of the trajectory, so you would
> expect the trajectory path to look pretty similar to the vector in terms
> of direction).
> 
> Jim


Jim,

   My bad, I forgot to change the 2D calculation. I will check in my changes 
and you can download the nightly
tomorrow morning. It will be 5.0u1 release (nightly).


Yuan

> 
> On 6/1/14 4:25 PM, Unidata IDV Support wrote:
> >>>> Hi:
> >>>>
> >>>> I've been running *backwards* trajectories with IDV5.0 and noticed
> >>>> that the trajectories are taking an unrealistic turn in the time step
> >>>> that begins their backwards integration (see attached). It is especially
> >>>> obvious when using datasets with longer time increments.  In this case,
> >>>> I'm using 3-h RAP data where I've aggregated the files by time when
> >>>> loading them.
> >>>>
> >>>> This bug could have preceded 5.0.  I just started running them
> >>>> today and figured I'd use the new release.
> >>>>
> >>>> Jim
> >>> Jim,
> >>>
> >>> This part of code not being changed for a while, I can reproduce in the 
> >>> 5.0 and I will fix it asap.
> >>>
> >>>
> >>> YUan
> >>
> >> Jim,
> >> I did see a bug in the calculation of backward trajectory, and checked in 
> >> a fix. You can try the nightly in 20 minutes, which is 5.0u1 release.
> >>
> >> I can not find the dataset you were using, I used the NAM80km, see the 
> >> attached image. I will do some comparison with gempak next week.
> >> Yuan
> >
> > Jim,
> >       I just committed another change and this should fix the bug you 
> > reported. I redo the 5.0 release, you should download and install the 5.0 
> > release.
> >       It is kind of interesting that I wrote this part of code on the 
> > flight from Madison to Denver, and now I have fixed a bug on the flight 
> > from Denver to New York.
> >
> > Yuan
> >
> >>>>
> >>>>
> >
> > Ticket Details
> > ===================
> > Ticket ID: ABK-864576
> > Department: Support IDV
> > Priority: Normal
> > Status: Closed
> >
> 
> 
> 


Ticket Details
===================
Ticket ID: ABK-864576
Department: Support IDV
Priority: Normal
Status: Open