fill missing value in array

Hi,

(unfortunatly, I have old matlab, where timeseries is not existing).

I have an array with data data_array, from which I have selected indeces K which I'd like to use.

I need to generate a new array dest_array , which will be with same length as the original one and populate values to it so that:

If I have selected index k (from K), the value dest_array[k]=data_array[k].

For all the missing enteries, I need to fill with values from previous known one.

What is the best way to do it?

Answer 1

[KSSV]

x = 1:100 ; 
y = rand(size(x)) ; 
% Introduce NaN's randomly 
idx = randperm(100,20) ; 
y0 = y ; 
y(idx) = NaN ; 
% Use interp1 
yi = interp1(x(~isnan(y)),y(~isnan(y)),idx)  ;
% compare 
plot(y0(idx),'r') 
hold on
plot(yi,'b')
legend('Original','filled')