How to create an index based on highest number in data
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Edward Johnsen
on 3 Sep 2018
Commented: Edward Johnsen
on 3 Sep 2018
I have a set of data (in a 360 * 1 vector) where i need matlab to read the first 2 lines, then assign the highest number in the first two lines a 1, and the other a 0, this needs to go on for each pair along the entire set. Any one got any ideas?
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Accepted Answer
Image Analyst
on 3 Sep 2018
If you have the Image Processing Toolbox, you can use blockproc() to process a pair of elements before jumping to the next pair down until it's gone all the way down the vector.
A = rand(360,1) % Random data for demo
% Define the function that we will apply to each block.
% In this demo we will take the max value in the block
% and create an equal size block where all pixels have the max value.
maxFilterFunction = @(theBlockStructure) max(theBlockStructure.data(:)) * ones(size(theBlockStructure.data), class(theBlockStructure.data));
% Block process the vector to replace every element in the
% 2 element block by the max of the values in the block.
blockSize = [2 1];
blockVector = blockproc(A, blockSize, maxFilterFunction) % Find elements of maxima.
% Construct output matrix.
B = [A, blockVector == A]
You'll get something like this:
B =
0.640283956310627 0
0.934334009701608 1
0.204451403319075 0
0.2808222992592 1
0.482153166343332 0
0.569773626383138 1
0.522844388080927 1
0.235050800044239 0
0.971156620920272 1
0.182306414206202 0
etc.
More Answers (1)
KSSV
on 3 Sep 2018
A = rand(10,1) ; % random data for demo
B = reshape(A,2,[])' ;
iwant = [B(:,1)>B(:,2) B(:,1)<B(:,2)]
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