How to interpolate data

Hello,

P=[NaN NaN NaN 163.626652810406 140.245221578496 143.291946126177 158.198843187782 179.073274059170 206.654075204109 255.461365237779 318.955295177489 396.993670297888 486.124439415540 587.818128810315 703.723462252509 831.059610098512 974.884947235331 1136.56020938783 NaN NaN] : it is 1*20 double

V= [148.527280000000 166.471365263158 184.415450526316 202.359535789474 220.303621052632 238.247706315790 256.191791578947 274.135876842105 292.079962105263 310.024047368421 327.968132631579 345.912217894737 363.856303157895 381.800388421053 399.744473684211 417.688558947368 435.632644210526 453.576729473684 471.520814736842 489.464900000000]

I want to know the specific V data when P is 500.

I try to use

V_specific = interp1(P,V,500);

but there is error message, I don't know what is the problem.

is there any methods to solve this problem?

Thanks

Answer 1

[Sylvain]

interp1 inputs must be real number (look at the section input arguments from the help.). Thus remove the NaN values from the input.

V_specific = interp1(P(4:end-3),V(4:end-3),500)

[hj lee]

Thans you very much!