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[IDV #AJF-799505]: fill value / missing value gets misinterpreted as data

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  • Subject: [IDV #AJF-799505]: fill value / missing value gets misinterpreted as data
  • Date: Fri, 11 Jan 2013 12:39:17 -0700
> Meaningful values are -30 to 30 roughly.
> 
> Where are the -9.99E8 values coming from? They occur where the original 
> dataset has fill or missing (below earths surface). So idv is somehow 
> converting fill or missing values to the -9.99E8.
> 
> 

In this case, the valid_range attribute should be used to let IDV know -9.998E8 
is not useful. Are you in any position to change this dataset?


Yuan
> Brian Mapes
> This message was typed on a cell phone, please forgive its terseness and any 
> errors.
> 
> On Jan 11, 2013, at 12:23 PM, "Unidata IDV Support" <address@hidden> wrote:
> 
> >> Hi Yuan. Thanks for taking this on.
> >>
> >> It's an online dataset.
> >> This bundle (attached) shows the problem easily with just 1 time level.
> >> Hope the problem isn't machine specific. (Im on a mac).
> >>
> >> See how the contour range and interval comes out non-useful because
> >> that is the range of data values. Yet the fill value, which is what
> >> should really be present in the undeground regions of earth, is actually
> >> 9.9999999E14f according to the metadata:
> >>
> >> float u(time=46752, lev=42, lat=361, lon=540);
> >> :_CoordinateAxes = "time lev lat lon ";
> >> :_FillValue = 9.9999999E14f; // float
> >> :missing_value = 9.9999999E14f; // float
> >> :long_name = "eastward wind component ";
> >
> > I don't get it. The data range is from -9.99E8 to 23.1 according to your 
> > attached image and file value is 9.999E14, and you suspect that the fill 
> > value somehow spoils the range of the data value. What is the data range 
> > you expected?
> >
> >
> > Yuan
> >> [cid:c15e1082-232c-405d-aa25-4c9f57e372fb@amazon.rsmas.miami.edu]
> >>
> >>
> >>
> >> Brian
> >>
> >>
> >>
> >> On Jan 11, 2013, at 11:19 AM, Unidata IDV Support wrote:
> >>
> >>>> Full Name: brian mapes
> >>>> Email Address: address@hidden
> >>>> Organization: u of miami
> >>>> Package Version: 4.0alpha1 build date:2012-12-26 08:14 UTC
> >>>> Operating System: Mac OS X
> >>>> Hardware: Java: home: 
> >>>> /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home 
> >>>> version: 1.6.0_37 j3d:1.3.1
> >>>> Description of problem: Loading this bundle, u850 appears to be 
> >>>> -9.999999E8 under the land surface.
> >>>>
> >>>> The dataset has 9.999999999e14 as the fill value and missing value, so 
> >>>> that is somehow being misinterpreted and spoiling the color range.
> >>>>
> >>>> I want to share bundles using this online dataset with a possible new 
> >>>> IDV user community on Jan 14, and I really wish this didn't make the 
> >>>> default colors always bad, requiring color table adjusting for each and 
> >>>> every display.
> >>> Brian,
> >>>  If the fill value is defined in the dataset, it should be recognized by 
> >>> the IDV. Could you send us a small sample file?
> >>>
> >>>
> >>> Yuan
> >>>
> >>> Ticket Details
> >>> ===================
> >>> Ticket ID: AJF-799505
> >>> Department: Support IDV
> >>> Priority: High
> >>> Status: Open
> >>
> >> Brian Mapes
> >> address@hidden
> >
> >
> > Ticket Details
> > ===================
> > Ticket ID: AJF-799505
> > Department: Support IDV
> > Priority: High
> > Status: Open
> >
> 
> 


Ticket Details
===================
Ticket ID: AJF-799505
Department: Support IDV
Priority: High
Status: Open