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#79: Handling and formatting of vector quantities in CF -----------------------------+---------------------------------------------- Reporter: lavergne | Owner: [email protected] Type: enhancement | Status: reopened Priority: medium | Milestone: Component: cf-conventions | Version: Resolution: | Keywords: vector -----------------------------+---------------------------------------------- Comment (by ngalbraith): Replying to [comment:60 davidhassell]: > Another idea that occurs to me, in the spirit of using existing functionality, might be to use the "cf_role" property, as is used for discrete sampling geometries. So your container variable could would have cf_role='vector'. Such a variable would then have vector_name='sea_ice_displacement'. A "vector_name" property in the absence of cf_role='vector' would not be treated in any special way. Using cf_role seems good because it's an existing concept. Could we also replace 'vector_name' with something like 'group_name' to make this easier to expand? Although we're starting with vectors, as the cf_role terms grow, the uses for this construct could be very broad. Going back to the example above, proposed in Sept '12, {{{ int ice_drift_vector; drift_vector:umbrella_name = "sea_ice_displacement_vector" ; drift_vector:long_name = "sea ice drift vector" ; drift_vector:i_component = "dX" ; drift_vector:j_component = "dY" ; drift_vector:i_j_direction = "dir" ; }}} I find the attribute names i_component and j_component completely opaque. CF is supposed to be human-readable, and these don't really convey any information, at least nothing intuitive. Was the idea to specify the components individually that we needed to identify whether this was a 2-d or 3-d vector? To me, a shared 'components' attribute would work just as well, and would be more flexible and concise. Could it be simplified to: {{{ int drift_vector; drift_vector:cf_role='vector'; drift_vector:group_name='sea_ice_drift_vector'; drift_vector:long_name = "sea ice drift vector" ; drift_vector: components = "dX, dY, dir" ; }}} The variables dX, dY, and dir would then be responsible for identifying themselves fully as to their role in the vector. I've read through the comments above and I see the i_ and j_component being proposed, but not adopted, and I don't find the rationale behind this. -- Ticket URL: <https://cf-pcmdi.llnl.gov/trac/ticket/79#comment:61> CF Metadata <http://cf-pcmdi.llnl.gov/> CF Metadata This message came from the CF Trac system. To unsubscribe, without unsubscribing to the regular cf-metadata list, send a message to "[email protected]" with "unsubscribe cf-metadata" in the body of your message.
