MATLAB: How to find a string within a matrix and output array index to variable

indexmatrix

First off, I hope that was titled right.

Secondly, here is my dilemma:

I have this matrix that is [1621×1] with 1-4 numbers in each row. I have a variable, called 'site' that has one of these numbers as its value.

I want to match the variable 'site',containing a number, to a number in a [1621×1] matrix and then find out what index the matching number from the [1612×1] matrix has.

I'm unclear about how to search the matrix for the specific value of 'site' and then return wherever site was found in the matrix as an index in a new variable.

I hope that I explained this right. If you need clarification, please ask!!!

Thanks!

Best Answer

your_matrix = 1621 x 1 matrix containing values 1 - 4
site = some value 1 - 4
indexes = find( your_matrix == site );

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dinfo = dir('*.txt');
nfiles = length(dinfo);
filenames = fullfile({dinfo.folder}, {dinfo.name});
IDs = cell(nfiles,1);
FCs = cell(nfiles,1);
intervals = cell(nfiles,1);
for K = 1 : nfiles
    
    filename = filenames{K};
    
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Note: this code does not assume that there is only one occurance of the information per file. It will find all of the occurance in each file, provided that the parts are all in the same order and none of the parts are missing.

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find( cellfun(@(C) numel(C) == 1 && C == 1, TEST) )

In the special case where each entry is only empty or a scalar, then

find( cellfun(@(C) C == 1, TEST) )

If you want to find a 1 anywhere in the cell:

find( cellfun(@(C) any(C == 1), TEST) )

Best Answer

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