MATLAB: Get the x-value of a point on curve

Question

I draw a curve between two vector of points, not a function, how can I get the x-value of a certain y-value of the curve?

Answer 1

When you say "get", do you mean from the vectors, or only from the curve?

If you mean from the data, you can do, for example

x(y==0.25)

(You might need to be careful if y is not exactly 0.25, due to floating point precision.)