How can i remove outliers from a 3d array using median standard deviation?

10 次查看（过去 30 天）

Joseph 2018-7-3

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/408640-how-can-i-remove-outliers-from-a-3d-array-using-median-standard-deviation

评论： Joseph 2018-7-4

Hi everyone, I have a 3d array E(i,j,k) in which k is the number of data in the dimension i and j. how can I remove the outliers from this 3d array using MAD(median absolute deviation)?

thank you in advance

6 个评论
显示 4更早的评论隐藏 4更早的评论

Image Analyst 2018-7-4

编辑：Image Analyst 2018-7-4

MAD is either the mean absolute deviation, or median absolute deviation - see wikipedia. Never heard of mean standard deviation, but I guess you could compute it if you had a population size. Which do you want? MAD is a very common outlier metric so you probably want that, but which MAD?

And what do you mean by removing outliers in a 3-D array. You cannot just get rid of those elements, but you can assign them to something, like the overall global mean, or zero, or the local median, or NAN, or something. What do you want?

Joseph 2018-7-4

apology, I meant median absolute deviation.

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

KSSV 2018-7-4

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/408640-how-can-i-remove-outliers-from-a-3d-array-using-median-standard-deviation#answer_327392

在 MATLAB Online 中打开

A = rand(30,36,100) ;   % some random data
[nx,ny,nz] = size(A) ;
for i = 1:nx
    for j = 1:ny
        T = squeeze(A(i,j,:)) ;
        themean = mean(T) ;
        sigma = std(T) ;
        idx = T>themean+3*sigma ;
        T(idx) = NaN ;
        idx = T<themean-3*sigma ;
        T(idx) = NaN ;
        A(i,j,:) = T ;
    end
end