Length's of matrix rows exclusing padding

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Hi, I have a matrix which looks a little like
X = [ 0 1 0 1 0 1 1 0 ]
[ 0 1 0 1 1 1 0 0 ]
[ 0 1 1 1 1 0 0 0 ]
This matrix has hundreds of rows so I cant do this manually but I wish to find the length of each vector in the array between the first 1 and the last 1 in each row
In this example it would be :
Y = [ 6 ]
[ 5 ]
[ 4 ]
Can somebody suggest how to do this.
Please note that I have simplified this problem and the numbers I have are not actually all 1's but vary between 1-10 ish.
Thanks :-)

Accepted Answer

Akira Agata
Akira Agata on 2 Mar 2018
If each row in X has at least one non-zero value, the following code can calculate Y.
X = [ 0 1 0 1 0 1 1 0;...
0 1 0 1 1 1 0 0;...
0 1 1 1 1 0 0 0 ];
[r,c] = find(X);
Y = splitapply(@(x) max(x)-min(x)+1, c, r);
  1 Comment
Nick Keepfer
Nick Keepfer on 2 Mar 2018
Wow, lightning fast answer!
Works perfectly, thank you very much Akira, you're awesome!

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