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20050707: Longitude Readout Not Correct

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  • Subject: 20050707: Longitude Readout Not Correct
  • Date: Thu, 07 Jul 2005 09:11:35 -0600
>From: "Salottolo Greg" <address@hidden>
>Organization: NTSB
>Keywords: 200507071251.j67Cpnjo022503 IDV longitude value readouts

Hi Greg-

>When I load this file and try to use the Create Bearing and Distance and 
>Create Location Indicator the latitude/longitude window indicates a 
>longitude of 200 something. The latitude values seem OK. Not sure what 
>is going on. If the file is not loaded the longitude values look OK.

The problem is that the GRIB file has longitudes listed as 0-360
instead of -180 to 180.  We take that information and create a
corresponding projection with values of 0-360.  The longitude
readout at the bottom normalizes to -180 to 180 (appropriately or not),
but the range and bearing and location indicator tools do not.

We'll have to look at the implications of normalizing either the
projection or the readout, but for now, you'll have to subtract
360 from the number in your mind to get the -180 to 180 value.

Thanks for pointing this out.

Don Murray
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