how to find closest values in array)
3 views (last 30 days)
Show older comments
I want to find closest numbers in array as shown in example a=[4 7 8 9 10 11 20 23 26 27 28 29 30 60] output first group 7 8 9 10 11 second group 26 27 28 29 30
3 Comments
Alex L
on 17 Jun 2017
Is your array always going to be sorted? To refine your question: You are looking for groups of integers in your array that have an absolute difference of 1 to either the preceding or the following integer in the array?
Accepted Answer
Image Analyst
on 17 Jun 2017
If you have the Image Processing Toolbox, you can use bwlabel to give an "ID number" to each group that has the minimum spacing. Then you can extract each of those labeled groups one at a time and put into a cell array.
a=[4 7 8 9 10 11 20 23 26 27 28 29 30 60] % Original, easy case: separate groups
% a=[4 7 8 9 10 11 12 25 26 27 28 29 30 60] % Tricky test case: groups adjacent/touching
% a=[6 7 8 9 10 11 12 25 26 27 28 29 30 31] % Tricky test case: groups touch each other and ends
diffs = diff(a)
minSpacing = min(diffs)
binaryLabels = diffs == minSpacing
% Label the groups
labeledgroups = bwlabel(binaryLabels)
% Extract each group
for k = 1 : max(labeledgroups)
thisGroupsIndexes = find(labeledgroups == k);
% Tack one more.
thisGroupsIndexes = [thisGroupsIndexes, thisGroupsIndexes(end)+1]
% Extract these elements from the original "a" vector
result{k} = a(thisGroupsIndexes)
end
0 Comments
More Answers (0)
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!