Re: [idvusers] Simple polylines in NetCDF files

• To: Mark Zimmerman <mark.zimmerman@xxxxxxx>
• Subject: Re: [idvusers] Simple polylines in NetCDF files
• From: Tom Whittaker <whittaker@xxxxxxxx>
• Date: Thu, 23 Jun 2011 10:38:30 -0500

Mark --

I don't know of any convention for polylines, but two other ideas come to mind:

1. use "track files" (see, for example:
<http://geon.unavco.org/unavco/IDV_datasource_track.html#a> might
work...

2. another approach would be to use the "shape" drawing that is built
into the IDV (although this is another, separate file).  You would use
the drawing tool and "File->import".  An example file, with two lines
in lat-lon coordinates:

<shapes>
  <polygon color="255,0,0" coordtype="LATLON" filled="false"
fulllatlon="false" linewidth="1.0" name="Glyph 1" pickable="true"
points="45.343544,-90.18899,45.311947,-90.12044,45.264553,-90.00653,45.264553,-89.96164,45.248753,-89.93868,45.185562,-89.75733,45.027576,-89.43984,44.980183,-89.30474,44.88539,-89.14668,44.759007,-88.87743,44.72741,-88.83254,44.64842,-88.6095,44.632618,-88.56496,44.60102,-88.498146,44.585224,-88.47586,44.569427,-88.43141,44.553627,-88.40915,44.553627,-88.38698,44.427242,-88.209404,44.41144,-88.165146,44.316654,-88.0105"
smooth="true" zposition="-0.995"/>
  <polygon color="255,0,0" coordtype="LATLON" filled="false"
fulllatlon="false" linewidth="1.0" name="Glyph 2" pickable="true"
points="43.921696,-88.05504,43.921696,-88.07697,43.96909,-88.25255,44.079678,-88.60468,44.12707,-88.78115,44.190266,-89.002205,44.221863,-89.1129,44.23766,-89.13522,44.23766,-89.15727,44.25346,-89.223724,44.25346,-89.24578,44.25346,-89.26784,44.269257,-89.290215,44.300854,-89.37914,44.300854,-89.401215,44.316654,-89.445724,44.33245,-89.46817,44.33245,-89.512344,44.348248,-89.512726,44.364048,-89.5573,44.364048,-89.57939,44.364048,-89.601494,44.379845,-89.624,44.395645,-89.668625,44.458836,-89.803116,44.506233,-89.93741,44.52203,-89.982216,44.553627,-90.02757,44.553627,-90.04974,44.569427,-90.09462,44.569427,-90.1168,44.585224,-90.11734,44.585224,-90.13953,44.61682,-90.273796,44.64842,-90.34159,44.64842,-90.3638,44.664215,-90.38662,44.664215,-90.40884,44.664215,-90.431046,44.680016,-90.43168,44.695812,-90.47676"
smooth="true" zposition="-0.995"/>
 </shapes>

tom

On Wed, Jun 22, 2011 at 2:54 PM, Mark Zimmerman <mark.zimmerman@xxxxxxx> wrote:
> Greetings:
>
> I have a 2D gridded data set that I am storing in a NetCDF file and
> which I have successfully rendered in IDV. Associated with this data
> set are several polylines which must be rendered in the view as well.
> So far, I have managed to do this by writing them to writing them to
> shapefiles which can be read into IDV. It would be less cumbersome if
> I could write the polyline data into the same NetCDF file that
> contains the gridded data but I have not yet stumbled upon a
> convention that will coerce IDV to recognize the data.
>
> I tried this (and failed):
>
> dimensions:
>        tdim = 361 ;
>        ... others ...
> variables:
>        double tlat(tdim) ;
>                tlat:long_name = "latitude" ;
>                tlat:units = "degrees_north" ;
>                tlat:axis = "Y" ;
>                tlat:standard_name = "latitude" ;
>        double tlon(tdim) ;
>                tlon:long_name = "longitude" ;
>                tlon:units = "degrees_east" ;
>                tlon:axis = "X" ;
>                tlon:standard_name = "longitude" ;
>        double term(tdim) ;
>                term:long_name = "Terminator" ;
>                term:units = "km" ;
>                term:coordinates = "tlon tlat" ;
>        ... others ...
>
> (term is just a dummy array containing zeroes)
>
> So, is there a convention for storing simple polylines in NetCDF
> files?
>
> Thanks,
> -- Mark
>
> _______________________________________________
> idvusers mailing list
> idvusers@xxxxxxxxxxxxxxxx
> For list information, to unsubscribe, visit: 
> http://www.unidata.ucar.edu/mailing_lists/
>



-- 
Tom Whittaker
University of Wisconsin-Madison
Space Science & Engineering Center (SSEC)
Cooperative Institute for Meteorological Satellite Studies (CIMSS)
1225 W. Dayton Street
Madison, WI  53706  USA
ph: +1 608 262 2759

• References:
  • [idvusers] Simple polylines in NetCDF files
    • From: Mark Zimmerman