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function rowVsCol
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%% Comparing indexing by row vs by column
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% Copyright 2015 The MathWorks, Inc.
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% Based on example by S. McGarrity
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%% Initializing variables
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N = 3000;
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thresh = 0.5;
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x1 = rand(N);
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x2 = rand(N);
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y1 = zeros(N);
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y2 = zeros(N);
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%% Using Row Major Indexing
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display('Using Row Major Indexing')
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tic
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for r = 1:N % Row
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for c = 1:N % Column
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if x1(r,c) > thresh
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y1(r,c) = x1(r,c);
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end
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end
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end
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toc
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%% Using Column Major Indexing
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display('Using Column Major Indexing')
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tic
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for c = 1:N % Column
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for r = 1:N % Row
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if x2(r,c) > thresh
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y2(r,c) = x2(r,c);
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end
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end
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end
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toc
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