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[THREDDS #IQR-260651]: Thredds NetCDF Subset Image Error

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  • Subject: [THREDDS #IQR-260651]: Thredds NetCDF Subset Image Error
  • Date: Mon, 23 Nov 2015 09:46:43 -0700
Danny,

Thanks for the detailed report. I can see the problematic output just looking 
at the basic netcdf4 output using Python, so there's clearly a bug here. I've 
opened an issue over on GitHub and you can keep an eye on it for further 
updates here: https://github.com/Unidata/thredds/issues/301

The only workaround I can offer, unfortunately, is to continue using netcdf3 
output, until we can run down why the files are coming out incorrect.

Ryan

> I have been using the Thredds data server to download satellite images.
> Sometimes I download a lot of images, so I use the NetCDF subset service
> and recently decided to use the netcdf4 files rather than the NetCDF
> files because they are much faster to download. Since I tried to use
> the NetCDF4 files, I have been running into some strange behaviour.
> Some of the data that comes out of the NetCDF4 files is scrambled -
> almost like it has the wrong dx or the wrong image width or something.
> The best I can figure is that something happens when the longitude of the
> western boundary is east of -140 degrees - all images come out scrambled.
> This is not entirely consistent - sometimes it happens even west of
> -140 degrees.  I have attached some screenshots of what is happening.

Ticket Details
===================
Ticket ID: IQR-260651
Department: Support THREDDS
Priority: Urgent
Status: Closed