The ts_tsdesc structure
A ts_tsdesc structure contains a time series (ts_timeseries)
and data structures for working with it. Among other things, ts_tsdesc tracks
the current element and holds two element buffers for creating two
elements.
Important: The two element buffers are shared
by the element-fetching functions. An element that is fetched is overwritten
two fetch calls later. Elements fetched by functions like ts_elem() should
not be explicitly freed. They are freed when the ts_tsdesc is
closed.
If you must look at more than two elements at a time, open a scan or use the ts_make_elem() or ts_make_elem_with_buf() routines to make a copy of one of your elements.
A ts_tsdesc structure is created by the ts_open() function and destroyed by the ts_close() procedure. It is used by most of the time series API routines.