Other attributes such as StcsCoords and StcsProps can be used to specify other Objects
to be returned by astRead. If more than one of these attributes is set non-zero, then
the actual Object returned by astRead will be a KeyMap, containing the requested
Objects. In this case, the Region representing the STC CoordinateArea will be stored in
the returned KeyMap using the key
" . If StcsArea is the only attribute to be set
non-zero, then the Object returned by astRead will be the CoordinateArea Region
The class of Region used to represent the CoordinateArea for each STC-S sub-phrase is
determined by the first word in the sub-phrase (the
" sub-phrase identifier
" ). The
individual sub-phrase Regions are combined into a single Prism, which is then
simplified using astSimplify to form the returned region.
Sub-phrases that represent a single value ( that is, have identifiers
" ) are considered to be be part of the STC
The TimeFrame used to represent a time STC-S sub-phrase will have its TimeOrigin attribute set to the sub-phrase start time. If no start time is specified by the sub-phrase, then the stop time will be used instead. If no stop time is specified by the sub-phrase, then the single time value specified in the sub-phrase will be used instead. Subsequently clearing the TimeOrigin attribute (or setting its value to zero) will cause the TimeFrame to reprsent absolute times.
The Epoch attribute for the returned Region is set in the same way as the TimeOrigin attribute (see above).