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Adding vectors

Question:

How can I provide access to vector variables?

Example:

Solution:

The following chunks of xml shows how to define a vector variable from the zonal and meridional components of wind in the COADS dataset. Once you've defined a vector variable in this manner, LAS will generate the appropriate graphics.

-- Before LAS v6.0 --

<datasets>
 <coads_climatology name="COADS Climatology" 
                    url="file:coads_climatology"
                    doc="doc/coads_climatology.html">
  <variables>
   <uwnd name="Zonal component of wind" units="M/S">
    <link match="/lasdata/grids/coads_climatology_grid"/>
   </uwnd>
   <vwnd name="Meridional component of wind" units="M/S">
    <link match="/lasdata/grids/coads_climatology_grid"/>
   </vwnd>
  </variables>
  <composite>
   <wind_vectors name="Wind vectors" js="VecVariable">
    <link match="../../variables/uwnd"/>
    <link match="../../variables/vwnd"/>
   </wind_vectors>
  </composite>
 <coads_climatology_cdf>
</datasets>

-- LAS v6.** --

<datasets>
 <coads_climatology name="COADS Climatology" 
                    url="file:coads_climatology"
                    doc="doc/coads_climatology.html">
  <variables>
   <uwnd name="Zonal component of wind" units="M/S">
    <link match="/lasdata/grids/coads_climatology_grid"/>
   </uwnd>
   <vwnd name="Meridional component of wind" units="M/S">
    <link match="/lasdata/grids/coads_climatology_grid"/>
   </vwnd>
  </variables>
  <composite>
   <wind_vectors name="Wind vectors">
    <properties>
     <ui>
      <default>file:ui.xml#VecVariable </default>
     </ui>
    </properties> 
    <link match="../../variables/uwnd"/>
    <link match="../../variables/vwnd"/>
   </wind_vectors>
  </composite>
 <coads_climatology_cdf>
</datasets>

Jonathan Callahan: Jonathan.S.Callahan@noaa.gov
Last modified: December 01, 2004