Hi Nan,
Encoding what I would regard as usage metadata into ancilliary variables is one solution, but I would much rather see a formalised metadata model for doing this. As you say a standard way of doing this is long overdue. My hope is that SeadataNet II starting later this year will take on and address this challenge. However, if anybody knows of anything already in existence that fits the bill it would be good to prevent yet another wheel being reinvented.
Cheers, Roy.
________________________________
From: cf-metadata-bounces at cgd.ucar.edu [cf-metadata-bounces at cgd.ucar.edu] On Behalf Of Nan Galbraith [ngalbraith at whoi.edu]
Sent: 04 August 2011 19:17
To: Steve Hankin; cf-metadata at cgd.ucar.edu
Cc: Jeff deLaBeaujardiere
Subject: Re: [CF-metadata] per-variable metadata?
Hi Steve -
I'm very interested in the background discussion on this -
any chance of bringing it into the foreground?
I'm using ancillary variables in 2-D in situ data files to describe
instruments and things like precision, accuracy, sample scheme,
etc.. For temperature files from moorings where different sensor
types are at different depths, I'd like to use something like
TEMP:ancillary_variables = "Instrument_manufacturer Instrument_model
Instrument_sample_scheme Instrument_serial_number TEMP_qc_procedure
TEMP_accuracy TEMP_precision TEMP_resolution";
and then
short INST_SN(depth) ;
INST_SN:long_name = "instrument_serial_number" ;
... etc., etc.
If there's going to be a standard way to do this, I'd really like to
know about it - sooner rather than than later.
Thanks -
Nan
On 8/4/11 11:35 AM, Steve Hankin wrote:
Hi Jeff,
Each variable in a CF file may possess an |ancillary_variables| attribute, that points to variables that have relationships (
http://cf-pcmdi.llnl.gov/documents/cf-conventions/1.5/cf-conventions.html#ancillary-data). To attach flags to a variable, use |ancillary_variables| to point to a variable that has |flag_values||| and |flag_meanings |attributes (
http://cf-pcmdi.llnl.gov/documents/cf-conventions/1.5/cf-conventions.html#flags).
We have started a discussion in the background, whether an example that illustrates this should be included in the CF documentation.
- Steve
=====================================================
On 7/14/2010 6:21 AM, Jeff deLaBeaujardiere wrote:
In another discussion, Steve Hankin wrote:
> CF generally favors attributes attached to variables over attributes attached to files
This reminds me of a question I wanted to ask: does CF have any conventions regarding how to handle data that contains multiple observed quantities with different quality flags, comment fields or other attributes for each quantity?
-Jeff DLB
_______________________________________________
CF-metadata mailing list
CF-metadata at cgd.ucar.edu<mailto:CF-metadata at cgd.ucar.edu>
http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
_______________________________________________
CF-metadata mailing list
CF-metadata at cgd.ucar.edu<mailto:CF-metadata at cgd.ucar.edu>
http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
--
*******************************************************
* Nan Galbraith (508) 289-2444 *
* Upper Ocean Processes Group Mail Stop 29 *
* Woods Hole Oceanographic Institution *
* Woods Hole, MA 02543 *
*******************************************************
--
This message (and any attachments) is for the recipient only. NERC
is subject to the Freedom of Information Act 2000 and the contents
of this email and any reply you make may be disclosed by NERC unless
it is exempt from release under the Act. Any material supplied to
NERC may be stored in an electronic records management system.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.cgd.ucar.edu/pipermail/cf-metadata/attachments/20110804/32e377c8/attachment.html>
Received on Thu Aug 04 2011 - 14:13:05 BST
