MATLAB: What is the faster mean to find a value of an array

search methodSymbolic Math Toolbox

Hi all,

I am looking for the fastest search inside an array. For example A3 array has 6250 elements:

[i,j] = find(A3(:,1) == Total);
Total = A3(i,j+1);

This method takes about a minutes to decide if the value "Total" is in the array A3 or not! which is long time 🙁

Is there any solution for the problem?

Thanks : )

Best Answer

Get a faster computer. Look at my results:

% Create sample array of 6250 elements
A3 = [randi(9, [1250,4]), ones(1250,1)];
numberOfElements = numel(A3)
Total = 8;
tic;
[i,j] = find(A3(:,1) == Total);
Total = A3(i,j+1);
toc
Elapsed time is 0.000033 seconds.

Is that 33 microseconds I'm getting? And you're getting minute(s)? Something doesn't add up.

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