Hugo Duncan wrote:
I think what you want is a piecewise constant series of (value, offset, end offset) tuples like this:
(42, 0, 9) (43, 9, 21) (44, 21, 30) ...
yes, that is what I am after. Two observations:
One inconvenience of this is that I assume it will always be necessary to have the next sample before inserting the current sample (so the end of the run can be specified), though this is not clear to me from the documentation (do I call inserter(42,0) or inserter(42,0,9)?).
The documentation is pretty explicit about this. inserter(42,0) inserts a 42 at offset 0 and only at offset 0. See the section "Populating a Series": http://tinyurl.com/gbg8u
And as an inefficiency, each timestamp gets stored twice (again, if I understand correctly).
That is true. It might be useful to define a series type where the end of one run is implicitly the beginning of another. Such a series would easily fit within the framework. Any ideas what such a thing might be called? For the purposes of genericity, the inserter would still need to accept runs in (value, offset, end offset) tuples, though. -- Eric Niebler Boost Consulting www.boost-consulting.com The Astoria Seminar ==> http://www.astoriaseminar.com