find nearest value on matrix
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find nearest value on matrix
Can someone help with this problem please..... for example a= 1250
matrix_b=[98 125 945 1005; 105 204 1105 1249; 200 250 1299 1450; 300 450 1350 1850]
want to find nearest equal or greater than a=1250 and the answer should be 1299
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Answers (2)
Roger Stafford
on 9 May 2016
result = min(b(b>=1250));
For this to work, there has to be at least one element of b that is greater than or equal to 1250.
1 Comment
Image Analyst
on 9 May 2016
Or, using the poster's names for variables:
closestValue = min(matrix_b(matrix_b >= a));
Walter Roberson
on 9 May 2016
Edited: Walter Roberson
on 11 Aug 2020
v = sort(matrix_b(:));
vidx = floor(interp1(v, 1:length(v), a, 'linear', 'extrap'));
if vidx ~= 0
result = v(vidx);
end
Or
v = sort(matrix_b(:));
vidx = find(v >= a, 1, 'first');
if ~isempty(vidx)
result = v(vidx);
end
or
v = sort(matrix_b(:));
[~, vidx] = histc(a, v);
if vidx ~= 0
result = v(vidx);
end
The middle of these is probably the easiest to think about, but it cannot be generalized to a list of a values like the other ones can (aside from the testing to be sure that a result was found.)
4 Comments
Walter Roberson
on 11 Aug 2020
The first of them did have a mistake, which I have now corrected.
Could you give an example that fails for the others?
Walter Roberson
on 11 Aug 2020
Another approach:
v(interp1(v,1:length(v), a, 'nearest', 'extrap'))
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