>From looking up the platform_orientation topic, I stumbled across all the >platform_ variables. I had a question and two concerns.
The question is about directional parameters. Where, if anywhere, is the reference direction specified (and how can the data be interoperable if it is not)? The units are degrees, but for platform_orientation, would that be from true north, magnetic north, or some direction specified elsewhere? I imagine there's a standard CF practice here. A concern is that there are six terms that have exactly the same definition (pitch angle, pitch rate, roll angle, roll rate, yaw angle, yaw rate). Once of them, yaw angle, is arguably exactly the same thing as platform_orientation, though maybe it depends on which authoritative source (and reference direction) one uses. A second concern is that the meaning of positive and negative values is not defined, particularly for these 6 standard names. Perhaps that's a variant on the reference direction question. Has anyone dealt with these such that they see the obvious solution? If not, what's the best way to make these useful, a suggestion on the mail list or a trac ticket? John ---------------- John Graybeal <mailto:[email protected]> phone: 858-534-2162 Product Manager Ocean Observatories Initiative Cyberinfrastructure Project: http://ci.oceanobservatories.org Marine Metadata Interoperability Project: http://marinemetadata.org _______________________________________________ CF-metadata mailing list [email protected] http://mailman.cgd.ucar.edu/mailman/listinfo/cf-metadata
