Replicating values a certain number of times

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Hello, I have a long array of data from 0 to 1959 in steps of 1. Is there any way to expand that data so that each value repeats x number of times? ie. if x is 4
new = 0 0 0 0 1 1 1 1 2 2 2 2 3 3 3 3...
I have compressed data and I want to be able to expand it with this approximation.
Thanks for your help!

Accepted Answer

Wayne King
Wayne King on 3 Dec 2013
Edited: Wayne King on 3 Dec 2013
There are a number of ways to do this.
One way use a constant interpolator:
x = 0:9;
h = ones(4,1);
xnew = zeros(40,1);
xnew(1:4:end) = x;
y = filter(h,1,xnew);
Another way use repmat()
x = (0:9)';
x = (repmat(x,1,4))';
x = reshape(x,40,1);

More Answers (2)

sixwwwwww
sixwwwwww on 3 Dec 2013
Edited: sixwwwwww on 3 Dec 2013
try this:
x = 1:100; % Values to be repeated
a = 4; % Number of times each value is repeated
b = repmat(x, 4);
b = reshape(b, 1, []); % Final result

Andrei Bobrov
Andrei Bobrov on 3 Dec 2013
Jos (10584)'s idea:
k = 1959;
n = 4;
x = floor((0:(k+1)*n-1)/n);

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