LabVIEW
B-spline curve: wrong interpolation
Solved!
@Kyle97330 wrote:
I'm pretty sure that the problem is that the spline fit needs to get the points to fit in order, but when you say you "sorted the points" what you are actually saying is that you sorted them by one of their coordinate values... NOT the order the points should appear in.
If your data looks somewhat circular all the time, you could try something like this instead:
1. Start by doing a circle fit. LabVIEW doesn't have one, but it has a sphere fit which works as a circle fit if you just use zero for all of the Z values.
2. Take the center of that circle. From there, calculate the angle to each point.
3. Sort the points by that angle.
4. Pass the points using that sorting to the spline algorithm.
If your data doesn't always look circular you might have to get more creative with the sorting, but you need to put them in actual order, not just sort by one column of values and disregard the order of the other column.
instead of fitting your data to a circle, you could use a 2d average to estimate the circle's center point:
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if I hadn't switched those two terminals
the result looks like this:
center - data
before: data - center
