Re: [thredds] Scan Aggregation vs. Feature Collection

Hi Kyle:

On 11/28/2012 3:07 PM, Kyle Wilcox wrote:
I've finally had time to test this out

New-style featureCollection FMRC: 
http://64.9.200.113:8080/thredds/catalog/LakeErieSST-FMRC/catalog.html
Old-style joinExisting Agg: 
http://64.9.200.113:8080/thredds/aoc.html?dataset=LakeErieSST-Agg

The TDS catalog entries: https://gist.github.com/4164765

The NetCDF files are one satellite pass per file.  The time dimension is 
unlimited with a length of 1 in the individual files.  The time units are 
seconds since epoch (all even seconds).

The joinExisting Agg works as expected just like in 4.2.  All of the services 
(including WMS) work.

ok


The featureCollection FMRC doesn't work quite as well, but I do get a valid 
dataset.
   * There are rounding issues when converting the original files' "seconds since 1970-01-01 
00:00:00" to the FMRC's "hours since 2012-03-11T08:00:00.000Z".
> Data is no longer on even seconds in the FMRC. Agg: http://64.9.200.113:8080/thredds/dodsC/LakeErieSST-Agg.ascii?time[0:1:132] VS. FMRC: http://64.9.200.113:8080/thredds/dodsC/LakeErieSST-FMRC/LakeErieSST-FMRC_best.ncd.ascii?time[0:1:132]

for "Best" im seeing these time coordinates:

 2012-03-11T08:00:00Z
 2012-03-14T06:55:00Z
 2012-03-17T07:25:00Z
 2012-03-18T08:05:00Z
 2012-03-18T08:10:00Z
 2012-03-20T07:55:00Z
 2012-03-22T07:40:00Z
 2012-03-23T06:45:00Z
 2012-03-26T07:20:00Z
 2012-03-27T08:00:00Z
 2012-05-03T08:20:00Z
 2012-05-06T07:15:00Z
 2012-05-10T08:25:00Z
 2012-05-11T07:30:00Z
 2012-05-14T08:00:00Z
 2012-05-15T08:45:00Z
 2012-05-17T08:30:00Z
 2012-05-18T07:35:00Z
 2012-05-18T07:40:00Z
 2012-05-19T08:20:00Z
 2012-05-20T07:25:00Z
 2012-05-23T07:55:00Z
 2012-05-24T07:00:00Z
 2012-05-25T07:45:00Z
 2012-05-26T08:25:00Z
 2012-05-27T07:30:00Z
 2012-05-28T08:15:00Z
 2012-05-30T08:00:00Z
 2012-10-01T06:45:00Z
 2012-10-01T06:50:00Z
 2012-10-08T06:55:00Z
 2012-10-19T08:15:00Z
 2012-10-21T08:00:00Z
 2012-10-22T07:05:00Z

these seem to match the original files.


   * The datasets has a "time_run" variable even though there are no "runs".  I can't 
remove the "time_run" variable from the resulting dataset using the protoDataset tag.
   * The "coordinates" attribute of the "sst" variable gets set to "time_run time 
lon lat".  I don't want 'time_run' to be part of the coordinates.  I can't change the attribute using 
the protoDataset tag.

yes, its an artifact of using FMRC. Ideally its harmless. We will look at the WMS problem.

   * The "File_Access" link takes me to a directory listing that doesn't apply 
the regex of the collection.  It lists all of the files in the directory rather than just 
the .nc4 files: 
http://64.9.200.113:8080/thredds/catalog/LakeErieSST-FMRC/files/catalog.html.

we will fix this

   * The WMS service does not work (it is a known issues with ncWMS and FMRC 
datasets... it does not handle the run dimension correctly).


we are looking at the WMS problem


Is a possible solution to create another option in the fmrcConfig's datasetTypes attribute to remove all 
concept of  a "run" from the dataset?  This will be useful for gridded files with no 
overlapping time.   <fmrcConfig datasetTypes="NoRunsPlzKThnx Files" />

Another solution could be to remove the concept of a "run" from a FMRC dataset 
if the calculated time_offset variable is filled with all zeros.

Thoughts?


What we need is a featureCollection type=GRIB for your case. I will think if we can add it quickly.


John