Re: [las_users] Request for selection of only one MISR band for LAS

[Roland Schweitzer <Roland.Schweitzer@xxxxxxxx>]

Penny,

Oots, Penny C. (LARC-E301)[SCIENCE SYSTEMS & APPLICATIONS INC.] wrote:

Roland,

 

Yes, band is what LAS and Ferret think of as the z-axis.  I tried the following:

 

In Thredds catalog, 1), I removed the three lines;

<variable name="Band">

      <attribute name="_CoordinateAxisType" value="GeoZ"/>

   </variable>

(when I used addXML.sh to regenerate the XML file for the modified Thredds entry, I got the error ‘File parsed.  No Lat/Lon grids found.’)

 

2)  I also tried  <variable name="Band">

      <attribute name="_CoordinateAxisType" value="GeoZ" coordValue="2"/>

   </variable>

Result: Got ‘No time axis

                 No time axis’ when I used addXML.sh to regenerate the XML file for the modified Thredds entry.  I got an XML output file but it referenced all four bands.

This will probably be right if band 2 is the first band in the z direction.  Do you still have the fake time axis in the TDS configuration?  We had to add something like this:


<variable name="mytime" type="double">
      <attribute name="units" value="days since 2003-01-01 00:00:00"/>
      <attribute name="_CoordinateAxisType" value="Time"/>
      <values>0 31 62</values>
   </variable>


(and example for the three test files I aggregated) to get addXML and LAS to recognize the aggregated time axis.  Right?

 

LAS:

3) I changed the LAS XML file from

<Band-z-id-56c64bcaa6 type="z" units="">

                <arange start="1" size="4" step="1" />

            </Band-z-id-56c64bcaa6>

 

to         <arange start="2" size="4" step="1" />  (shows bands 2-5 on interface)

          <arange start="2" size="1" step="1" />  (no bands, get err-  Illegal Limits   Sorry ...  There are no data available at 01-OCT-2006 00:00    The data begin at 16-DEC-2005 12:00 and continue to 21-SEP-2006 12:00

<arange start="2" size="4" step="4" />  (shows bands, 2, 6,10,14)

 4)  <Band-z-id-56c64bcaa6 type="z" units="">

    <v>2</v>

    <v>2</v>

  </Band-z-id-56c64bcaa6>

Result:  Only shows 2 on the interface, displays plot for first month, gets error on display of second mth:

This should also have worked, but seems to suffer from the problem of the missing time axis definition in the TDS configuration.

Can you check on that time axis definition for me?

What you really need is the TDS "logicalView" capability.  Last I knew it was not yet implemented.  I will inquire with Unidata about the status.

Roland

Illegal Limits

Sorry ...

    There are no data available at 01-OCT-2006 00:00

    The data begin at 16-DEC-2005 12:00 and continue to 21-SEP-2006 12:00

Please try again with a time that lies within this range.

 

Hope this helps.

 

Penny

---

From: Roland Schweitzer [mailto:Roland.Schweitzer@xxxxxxxx]
Sent: Friday, November 02, 2007 2:19 PM
To: Oots, Penny C. (LARC-E301)[SCIENCE SYSTEMS & APPLICATIONS INC.]
Cc: oar.pmel.las_users@xxxxxxxx
Subject: Re: [las_users] Request for selection of only one MISR band for LAS

 

Penny,

What exactly did you try?  Is the band what LAS and Ferret think of as the z-axis?  If so it seems you should be able to create LAS configuration using only one point on that axis or use THREDDS to completely replace the axis definition using an ncML description to create the new axis.

Before I start trying a bunch of things, I'd like to know what's already been tried.

Roland

Oots, Penny C. (LARC-E301)[SCIENCE SYSTEMS & APPLICATIONS INC.] wrote:

Roland,

Remember this?  Unfortunately I have been asked to only show band 2

data.  I've tried some things in the Thredds catalog as well as in the

LAS configuration file for this dataset, but with no success.  Can you

suggest a way to just serve the band 2 data?  Preferably without the

'Select Depth' box showing up on the interface?

Thanks once again,

Penny

Date: Mon, 11 Jun 2007 09:04:18 -0500

From: "Roland Schweitzer" <weathertop.consulting@xxxxxxxxx>

To: p.c.oots@xxxxxxxxxxxxx,

    oar.pmel.las_users@xxxxxxxx,

    Steven.C.Hankin@xxxxxxxx

Subject: Re: Fwd: Re: [las_users] AddXML : "File parsed. No Lat/Lon 

grids found."

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definitions=main-0706100062

Penny,

Here is an example that answers both your questions (how to get addXML

to recognize the grids and how to treat all the individual files as 

one big data set).  My example only aggregates three months.  You can 

just add on months to get the full time range you want.

These files are weird.  Time has been averaged out of the data.  

However, a time axis still exists in the file even though it's not 

used by any of the variables.  I made up a new variable name for the 

new synthetic time axis.  I picked "mytime".  You probably should come

up with a better name.  And you should verify that I have actually 

done something that makes sense according to your understanding of  

the data. :-)

Roland

<dataset name="misraer" ID="misraer" serviceName="gridded"

   urlPath="test/MISR_aggregation">

      <netcdf

xmlns="<http://www.unidata.ucar.edu/namespaces/netcdf/ncml-2.2>http://ww

w.unidata.ucar.edu/namespaces/netcdf/ncml-2.2">

         <aggregation type="joinNew" dimName="mytime">

            <netcdf

location="/home/porter/rhs/UserQuestions/PennyOots/MISR_AM1_CGAS_0_5_DEG

_JUN_2003_F02_0025.nc"/>

            <netcdf

location="/home/porter/rhs/UserQuestions/PennyOots/MISR_AM1_CGAS_0_5_DEG

_JUL_2003_F02_0025.nc"/>

            <netcdf

location="/home/porter/rhs/UserQuestions/PennyOots/MISR_AM1_CGAS_0_5_DEG

_AUG_2003_F02_0025.nc"/>

        <variableAgg name="Optical_depth_average"/>

        <variableAgg name="Optical_depth_average_count"/>

        <variableAgg name="Optical_depth_standard_deviation"/>

        </aggregation>

   <variable name="Band">

      <attribute name="_CoordinateAxisType" value="GeoZ"/>

   </variable>

   <variable name="mytime" type="double">

      <attribute name="units" value="days since 2003-01-01

00:00:00"/>

      <attribute name="_CoordinateAxisType" value="Time"/>

      <values>0 31 62</values>

   </variable>

</netcdf>

</dataset>