MATLAB Answers

How can I count the number of 1 after every element of the vector?

1 view (last 30 days)
I have this vector of 1 and 0:
X= [1 1 1 1 0 0 1 1 0 1 0 1 0 0 1 1]
I want to create a vector Y that counts for every element of X the number of 1 that there are after it (including the 1 of the element, if is 1)
So the vector Y should be:
Y=[4 3 2 1 0 0 2 1 0 1 0 1 0 0 2 1]
How can I do that?
thank you!

  0 Comments

Sign in to comment.

Accepted Answer

Stephen Cobeldick
Stephen Cobeldick on 17 Feb 2020
Edited: Stephen Cobeldick on 17 Feb 2020
>> X = [1,1,1,1,0,0,1,1,0,1,0,1,0,0,1,1]
X =
1 1 1 1 0 0 1 1 0 1 0 1 0 0 1 1
>> Z = cumsum([true,diff(X)>0]);
>> F = @(v){flip(cumsum(flip(v)))};
>> Y = cell2mat(accumarray(Z(:),X(:),[],F)).'
Y =
4 3 2 1 0 0 2 1 0 1 0 1 0 0 2 1

  0 Comments

Sign in to comment.

More Answers (0)

Sign in to answer this question.