split binary array based on value 1
1 view (last 30 days)
Show older comments
Jasper
on 31 Aug 2015
Answered: Azzi Abdelmalek
on 31 Aug 2015
Hi,
I have a binary array that I would like to split up into several others, each starting with a '1'. I almost have it to work, except the sizes do not match and mat2cell does not work. Please help me with the last bit, thanks!
Jasper
a = [ 1 0 0 0 1 0 0 0 0 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0]';
indices = find(a(:,1)~= 0); % gives 1,5,11,16 and is correct
sizes = diff([indices' size(a, 1)]);% gives 4,6,5,13 instead of 4,6,5,14!
mat2cell(a, sizes, size(a, 1)); % fail!
0 Comments
Accepted Answer
More Answers (2)
Image Analyst
on 31 Aug 2015
I don't see any splitting going on - it's not splitting the array into multiple other arrays. What I see is you counting the zeros and ones as a unit. If you have the Image Processing toolbox, you can just find the sizes of the 0's and add 1:
a = [ 1 0 0 0 1 0 0 0 0 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0]';
labeledArray = bwlabel(a==0);
measurements = regionprops(labeledArray, 'Area');
lengths = [measurements.Area]+1
In the command window:
lengths =
4 6 5 14
0 Comments
Azzi Abdelmalek
on 31 Aug 2015
a = [ 1 0 0 0 1 0 0 0 0 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0]';
ii1=strfind(a',[1 0]);
ii2=strfind([a' 1],[0 1]);
out=arrayfun(@(x,y) a(x:y),ii1,ii2,'un',0);
celldisp(out)
0 Comments
See Also
Categories
Find more on Matrices and Arrays in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!