Re: Intersection of 2 curves


dtshedd@xxxxxxxxx wrote:
I am trying to locate a numerical technique to find the intersection of
2 curves. These are defined by tables of data rather than equations.
The data can be fitted with a 2nd degree polynomial, and only intersect
at one point. Both curves have positive slopes, though one has a
larger slope than the other.

If the y values of each curve are all tabulated at the same x values,
just tabulate the differences. The curves intersect where the
difference changes sign. You could then interpolate between the
differences either side of zero to get a better estimate. If your
curves only have a small quadratic term, a linear interpolation might
be OK; if not, 2nd degree polynomial.

Jon

.

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