[GEMPAK #XYG-194160]: NEXR2RHI image artifacts - what am I doing wrong?

Great stuff Greg, I appreciate you passing it along to me.  I'll make the 
change for the upcoming GEMPAK 6.6 release.


> Michael,
> I talked to Chiz about this problem and he looked into it for me. The problem 
> seem to be in the rnex2.c file where there is a check against >= BADVAL. The 
> version of this routine in the GEMPAK6.2.0 and GEMPAK6.4.0 distributions has 
> == BADVAL. This seemed to clear up the problem for me. I'm attaching Chiz' 
> version of this c routine. You may want to replace this file in current and 
> future distributions.
> 
> Thanks,
> Greg
> 
> 
> 
> 
> 
> On Apr 6, 2012, at 10:33 AM, Unidata GEMPAK Support wrote:
> 
> > Greg,
> >
> > The NEXR2RHI program is a Unidata addition to GEMPAK, authored by the 
> > developer who was here before me.  I checked RSL updates and for any CRAFT 
> > file format changes and found no leads.
> >
> > However, I was able to control the off contouring with INTERP and CONTUR.   
> > I recommend turning OFF interpolation and limiting contouring to 2 or less. 
> > I've been able to produce acceptable RHI plots with CONTUR = 0, 1 or 2, 
> > without the contouring artifacts.  Setting it to 3 or greater re-introduced 
> > the errors.
> >
> > Please give this a try and let me know how it works for you.  It's not a 
> > solution which addressed the cause, only the symptom, but hopefully it 
> > works well enough for what you plan to show.  I'm sorry I don't have a 
> > better solution for you.
> >
> > Michael
> >
> >
> >
> >> Michael,
> >> Thanks for the quick update - much appreciated. I understand the meeting 
> >> prep and priority. I'll look forward to hearing more from you after the 
> >> meeting.
> >>
> >> Thanks!
> >> Greg
> >>
> >> On Mar 30, 2012, at 2:16 PM, Unidata GEMPAK Support wrote:
> >>
> >>> NAWIPS/GEMPAK developers at NCEP said they have seen something similar in 
> >>> GDCROSS before, when selecting a grid cross-section, and it was caused 
> >>> then by an over-filled array, so that's likely the case with NEXR2RHI.  
> >>> Unfortunately I won't be able to time on this until the middle of next 
> >>> week, so I'll try to get back to you Tues or Weds.  Sorry about the 
> >>> delay, we have a committee meeting on Monday and Tuesday which I'm 
> >>> swamped with at the moment.
> >>>
> >>> Michael
> >>>
> >>>
> >>>> Michael,
> >>>> Any progress on this issue yet? I have PIs who are counting on being 
> >>>> able to use a GEMPAK script to create these cross-sections for a field 
> >>>> campaign starting in a few weeks.
> >>>>
> >>>> Thanks,
> >>>> Greg
> >>>>
> >>>>
> >>>> On Mar 23, 2012, at 4:11 PM, Unidata GEMPAK Support wrote:
> >>>>
> >>>>> Yikes, that indeed does look awful.  I'm seeing the same artifacts and 
> >>>>> turning interpolation off (INTERP=n) doesn't remove them all.
> >>>>>
> >>>>> Will update you when I know more.
> >>>>>
> >>>>> -Michael
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>>> I'm trying to plot x-sections from the NEXRAD Level II radars of 
> >>>>>> reflectivity and I'm getting a lot of artifacts in the image that 
> >>>>>> render the product useless. Attached is a screen shot I created from 
> >>>>>> data from yesterday from the KHTX radar in Huntsville. Below are the 
> >>>>>> values I used in NEXR2RHI to create this plot:
> >>>>>>
> >>>>>> GEMPAK-NEXR2RHI>l
> >>>>>> CXSTNS   = 34.75;-86.6>33.5;-86.8
> >>>>>> GVCORD   = hght
> >>>>>> PTYPE    = lin
> >>>>>> YAXIS    = 0/20000
> >>>>>> CINT     = 0
> >>>>>> SCALE    = 0
> >>>>>> LINE     = 1
> >>>>>> BORDER   = 1
> >>>>>> TITLE    = 1/-2/RHI Base Reflectivity Level II ^
> >>>>>> CLEAR    = YES
> >>>>>> DEVICE   = XW
> >>>>>> TEXT     = 1
> >>>>>> PANEL    = 0
> >>>>>> CLRBAR   = 1
> >>>>>> CONTUR   = 3/2
> >>>>>> FINT     = 4/4/64
> >>>>>> FLINE    = 0;30-7
> >>>>>> CTYPE    = f
> >>>>>> RADFIL   = /export/ldm/data/gempak/nexrad/craft/KHTX/KHTX_20120322_2103
> >>>>>> RADPARM  = dz
> >>>>>> RADTIM   = last
> >>>>>> INTERP   = y
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>> I've tried different radars as well as different values (orientations) 
> >>>>>> for the cxstns parameter but most produce artifacts like those shown 
> >>>>>> in this image. What am I doing wrong?
> >>>>>>
> >>>>>> Thanks,
> >>>>>> Greg
> >>>>>>
> >>>>>> -----------------------------------------------------------
> >>>>>> Greg Stossmeister
> >>>>>> Head - Collaborative Tools and Metadata Group
> >>>>>> NCAR/Earth Observing Laboratory (EOL)
> >>>>>> Telephone: (303)497-8692  Facsimilie:(303)497-2044
> >>>>>> e-mail: address@hidden
> >>>>>> Mailing Address:          Shipping Address:
> >>>>>> NCAR/EOL                    UCAR Foothills Lab 1
> >>>>>> P.O. Box 3000               3450 Mitchell Ln
> >>>>>> Boulder, CO 80307      Boulder, CO 80301
> >>>>>> ------------------------------------------------------------
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>
> >>>>>
> >>>>> Ticket Details
> >>>>> ===================
> >>>>> Ticket ID: XYG-194160
> >>>>> Department: Support GEMPAK
> >>>>> Priority: Normal
> >>>>> Status: Open
> >>>>>
> >>>>
> >>>> -----------------------------------------------------------
> >>>> Greg Stossmeister
> >>>> Head - Collaborative Tools and Metadata Group
> >>>> NCAR/Earth Observing Laboratory (EOL)
> >>>> Telephone: (303)497-8692  Facsimilie:(303)497-2044
> >>>> e-mail: address@hidden
> >>>> Mailing Address:          Shipping Address:
> >>>> NCAR/EOL                    UCAR Foothills Lab 1
> >>>> P.O. Box 3000               3450 Mitchell Ln
> >>>> Boulder, CO 80307      Boulder, CO 80301
> >>>> ------------------------------------------------------------
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>
> >>> Ticket Details
> >>> ===================
> >>> Ticket ID: XYG-194160
> >>> Department: Support GEMPAK
> >>> Priority: High
> >>> Status: Open
> >>>
> >>
> >> -----------------------------------------------------------
> >> Greg Stossmeister
> >> Head - Collaborative Tools and Metadata Group
> >> NCAR/Earth Observing Laboratory (EOL)
> >> Telephone: (303)497-8692  Facsimilie:(303)497-2044
> >> e-mail: address@hidden
> >> Mailing Address:          Shipping Address:
> >> NCAR/EOL                    UCAR Foothills Lab 1
> >> P.O. Box 3000               3450 Mitchell Ln
> >> Boulder, CO 80307      Boulder, CO 80301
> >> ------------------------------------------------------------
> >>
> >>
> >>
> >>
> >>
> >>
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: XYG-194160
> > Department: Support GEMPAK
> > Priority: Urgent
> > Status: Open
> >
> 
> -----------------------------------------------------------
> Greg Stossmeister
> Head - Collaborative Tools and Metadata Group
> NCAR/Earth Observing Laboratory (EOL)
> Telephone: (303)497-8692  Facsimilie:(303)497-2044
> e-mail: address@hidden
> Mailing Address:          Shipping Address:
> NCAR/EOL                    UCAR Foothills Lab 1
> P.O. Box 3000               3450 Mitchell Ln
> Boulder, CO 80307      Boulder, CO 80301
> ------------------------------------------------------------
> 
> 
> 
> 
> 
> 
> 


Ticket Details
===================
Ticket ID: XYG-194160
Department: Support GEMPAK
Priority: Urgent
Status: Open