Radious of curvature calculation from dicreate data set ?

Hi all,

I have 2-dimensional data set in X and Y such as

X= [0.1, 0.3, 0.4, 0.5, 0.08]

Y= [0.2, 0.4, 0.1, 0.3, 0.06]

FYI.Actually I want the calculate the radious of curvature from the 2D blue dot point data set in the attached figure. I know all the blue dot point coordinates in X,Y like above given data.

How I can calculate the radius of curvature from the data set? Thanks in advance

Answer 1

[Image Analyst]

Fit the data to an exponential decay. That should give you better parameters to use than the radius of curvature. I think this is the best option. If you really need the radius of curvature, take the second derivative analytically using the formula my fit gives you and then evaluate it at the x position you'd like.

Alternatively you can fit just the data in the corner of the curve to a circle using the FAQ:

https://matlab.fandom.com/wiki/FAQ#How_can_I_fit_a_circle_to_a_set_of_XY_data.3F

That will give you the radius of a circle fit to the data. But be sure you don't include the straight parts, which have a radius of curvature of infinity.