How Can I randomly select 10% of my array values and replace it with N/A or zero

Hello Everyone, I hope you are doing well.

I have the dataset 250x1000 attached below. i want to randomly select 10% of element from may array and replace it with N/A or zero. How can i do that in matlab

Any help appreciated :)

Answer 1

[KSSV]

Let A be your 250x1000 array.

N = numel(A) ; % total number of elements 
idx = randsample(N,round(10/100*N)) ;  % select 10% of indices randomly 
A(idx) = 0;   % replace with 0 

[Med Future]

@KSSV and what about N/A? How can i replace with N/A

and if i want to get 15% where i can change

[KSSV]

N/A is NaN you mean?

To have 15% change thi line:

idx = randsample(N,round(10/100*N)) ;  % select 10% of indices randomly 

[Med Future]

@KSSV yeh i means NAN Who can i replace NAN instead of zero?

[Med Future]

@KSSV What is different between randperm and randsample command?

[KSSV]

It is straight forward, use NaN instead of zeros. Simple.

A(idx) = NaN ;  % replace with NaN

[KSSV]

Read doc, runt he function and you can see the difference.