How can I find index of nearest value to specific number

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Farshid Daryabor 2020-3-26

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评论： Farshid Daryabor 2020-3-26

Please find attached file I want to find first index of arrays < 5 and then remove them from matrix (I want to filter arrays less than 5). I really appreciate any help.

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Adam 2020-3-26

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在 MATLAB Online 中打开

The question in your title is different to in the body so I'm not sure which is the one you actually mean, but

doc find

works for the one in the question body, e.g.

find( myArray < 5, 1 );

and for finding the nearest element to some value

[~, idx] = min( abs( myArray - 5 ) );

would find the value closest to 5 in myArray.

Farshid Daryabor 2020-3-26

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I tried your comment, but it is not what I am looking for. If you open file at the top rows of the matrix is the values less than 5 I want to have a new matrix that start with the values greater than 5, whilst the values less than 5 replace with NaN.

Farshid Daryabor 2020-3-26

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The comment below is what I am looking for; thanks

Pnew = reshape(P,[],1);

idx = find(Pnew<5);

Pnew(idx)=NaN;

Akira Agata 2020-3-26

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Looking at your attached data, the matrix is 143-by-417 and the 1st rows contains many >5 values.

Could you tell us more details on the problem you are facing and on what the desired output matrix looks like.

Farshid Daryabor 2020-3-26

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the attached file is the water depth and for further analysis I want to avoid and filter the depth less than 5 m becuse of inaccuracy in measurement by the marine instrument.

Farshid Daryabor 2020-3-26