Added smoothing to graph authoring tool
Sam Fentress
The graph authoring tool now contains a basic implementation of editable
smoothing. In the Data tab, under the time limit selection, there is a
new "Smoothing" checkbox that contains two parameters. Checking the box
will apply smoothing as the last filter applied. In the case of the
velocity graph, this means that it will smooth the output of the
differentiation filter, not the data going into that filter.
Eventually the order of filters will be directly authorable.
The smoothing algorithm applied is the Holt's two-parameter exponential
smoothing model. I wasn't able to find much information about this, so
it's a little tricky to understand exactly what the parameters are
doing. Some experimentation, however, shows that (perhaps
counter-intuitively) the lower the values are the more the data are
smoothed. Making the value of "level" equal to zero completely flattens
the graph. Making the value of "trend" equal or close to zero gives you
pretty straight positive or negative trend lines. Making trend > 3 or
so appears to make the data fluctuate quite wildly.
Once we start having a newer, more flexible system for adding filters,
there will be more impetus to develop other smoothing algorithms for
different situations, as we were discussing yesterday.
Let me know if you have any questions, or encounter any bugs,
Sam