[NeXus-tech] NXcollimator has two "frequency" entries

[Pete Jemian]

There are two "frequency" entries in the metaDTD definition of NXcollimator.

    <frequency type="NX_FLOAT">
        {Frequency of oscillating collimator}?
    </frequency>
    <NXlog name="frequency">
        {Log of frequency}?
    </NXlog>

These were translated (by hand) to the NXDL

    <field name="frequency" type="NX_FLOAT">
        <doc>Frequency of oscillating collimator</doc>
    </field>
    <group type="NXlog" name="frequency">
        <doc>Log of frequency</doc>
    </group>

and thus there are now two named entries for "frequency." 
Depending on how group elements are translated into XSD,
this most likely results in an error.  Using a template from other similar
contexts (NXcrystal, NXfilter, NXmoderator, NXmonitor, NXsample),
the second named element would be name="frequency_log" but our intent
in first setting out NXDL was not to make corrections in the metaDTD.

How best to proceed?  My vote would be to call this "frequency_log"
so as not to generate an XSD error but this might change the rules on
existing NeXus files.

Pete

[Pete at regitte,3017,~/NeXus-xslt]$ grep _log ../base_classes/*.xml | grep 
-v nxdl | grep NXlog
../base_classes/NXcrystal.xml:  <temperature_log type="NXlog">
../base_classes/NXfilter.xml:   <temperature_log type="NXlog">
../base_classes/NXmoderator.xml:        <temperature_log type="NXlog">
../base_classes/NXmonitor.xml:  <integral_log type="NXlog" units="">
../base_classes/NXsample.xml:   <temperature_log type="NXlog">
../base_classes/NXsample.xml:   <magnetic_field_log type="NXlog">
../base_classes/NXsensor.xml:   <value_log type="NXlog">
../base_classes/NXsensor.xml:   <value_deriv1_log type="NXlog">
../base_classes/NXsensor.xml:   <value_deriv2_log type="NXlog">


-- 
----------------------------------------------------------
  Pete R. Jemian, Ph.D.                <jemian at anl.gov>
  Beam line Controls and Data Acquisition, Group Leader
  Advanced Photon Source,   Argonne National Laboratory
  Argonne, IL  60439                   630 - 252 - 3189
-----------------------------------------------------------
     Education is the one thing for which people
        are willing to pay yet not receive.
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