Finding Distance Between Points and a Curve

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Jonathan Pinko on 24 Feb 2020
Commented: Adam Danz on 26 Feb 2020
Hi All,
I have attached two plots I would like to analyze. In both of these plots, I would like to find the vertical distance between most of the points (excluding the points that are left of the curves) and the curve. As in, for each point, I would like to imagine a vertical line extending from the point to the curve, and then find the length of this line. Ultimately, I would like to have produced two column vectors, a and b, for each of the two plots, and then create one final column vector, a^2+b^2.
Does anybody have any insight as to how to do this?
Please let me know if I could provide more helpful information as well.
Thanks

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Adam Danz on 24 Feb 2020
One approach would be
1. use min(redline), max(redline) to get the lower and upper bounds of the x values for the red line.
2. determine which scatter points are within those bounds and store their x-values and store them in a vector as xq.
3. use vq = interp1(x,v,xq) to interpolate the redline (x,y) coordinates at the new xq values to get the corresponding vq values.
4. Then subtract vq from the y values of the scatter points to get the vertical distance.
Jonathan Pinko on 25 Feb 2020
Adam Danz's approach worked perfectly.
Thank you.
Adam Danz on 26 Feb 2020
Thanks for the feedback! Sounds like you implemented it without any problems.