A base interface for metadata applicable to coordinate system objects.
The metadata items “Abbreviation”’, “Alias”, “Authority”, “AuthorityCode”, “Name” and “Remarks” were specified in the Simple Features interfaces, so they have been kept here.
This specification does not dictate what the contents of these items should be. However, the following guidelines are suggested:
When CS_CoordinateSystemAuthorityFactory is used to create an object, the “Authority” and “AuthorityCode” values should be set to the authority name of the factory object, and the authority code supplied by the client, respectively. The other values may or may not be set. (If the authority is EPSG, the implementer may consider using the corresponding metadata values in the EPSG tables.)
When CS_CoordinateSystemFactory creates an object, the “Name” should be set to the value supplied by the client. All of the other metadata items should be left empty.
This is a non-instantiable abstract class.
Most subclasses will have a set of optional parameters in their “create” method to set the metadata fields. These parameters are, in order:
authority: authority name
#authority_code: authority-specific identification code
abbreviation: an abbreviation
alias: an alias
remarks: provider-supplied remarks.
extensions: a hash of extension keys and values
Gets the abbreviation.
Gets the alias.
Gets the name.
Gets the provider-supplied remarks.
Gets the value of a keyed extension. This is not part of the OGC spec, but it is supported because some coordinate system databases (such as the spatial_ref_sys table for PostGIS 2.0) include it.
# File lib/rgeo/coord_sys/cs/entities.rb, line 550 def extension(key_) @extensions[key_.to_s] end