How to retain duplicate while using ScatteredInterpolant

I want to retain duplicates when using ScatteredInterpolant because I am getting warning:"Warning: Duplicate data points have been detected and removed - corresponding values have been averaged. "

[shravani banerjee]

Did you found your answer as I too have the same problem?

Answer 1

[John D'Errico]

1-d is sufficient to explain here.

x = [1 2 3 3 4 5];
y = [1 2 3 4 5 6];

There is a replicated x, with two distinct values of y. Exactly what do you think "retaining the duplicate" means here? What value of y should be interpolated when x==3?

A property of interpolation is that for any given x, if one of the original data points is interpolated, you should get out exactly the same value as went in. (At least, exact to within floating point trash.)

[Aristo]

Let me explain, if you have a array

x= [1,2,3,1,1,4,5,6,1,7]

then , if I use ScatterInterpolant , x becomes:

x=[1,2,3,4,,5,6,7]

but I need x to be:

 x= [1,2,3,1,1,4,5,6,1,7]

[Walter Roberson]

You have not answered the question about which value of y should be interpolated.

Answer 2

[Francesc Purroy]

In some cases you can have a set of x and y data where the values of x and/or y are repeated as Aristo was showing. A simple way around is to add some noise to your data as with randn then ScatterInterpolant does not consider the values to be equal and it works for me.