Replace NaN with median per column

11 ビュー (過去 30 日間)
Konvictus177
Konvictus177 2021 年 8 月 10 日
回答済み: Yazan 2021 年 8 月 10 日
Hi,
I have a matrix where I have NaN values in a few columns.
I would like to fill the NaN values with the median value of that column. How do I do that?

回答 (4 件)

KSSV
KSSV 2021 年 8 月 10 日
編集済み: KSSV 2021 年 8 月 10 日
Read about fillmissing.
Or USe:
A = rand(20,1) ; % data for demo
A(randperm(20,5)) = NaN ; % insert nans
M = nanmedian(A) ; % get median
A(isnan(A)) = M % replace nans with medians

Wan Ji
Wan Ji 2021 年 8 月 10 日
It is convenient to use fillmissing function to get what you want
matOut = fillmissing(matrixIn, 'linear', 'EndValues','nearest')
  4 件のコメント
Yazan
Yazan 2021 年 8 月 10 日
This does linear interpolation of neighboring non-nan values. It does not replace nan values with the median.
Wan Ji
Wan Ji 2021 年 8 月 10 日

サインインしてコメントする。


Stephen23
Stephen23 2021 年 8 月 10 日
編集済み: Stephen23 2021 年 8 月 10 日
M = randi(3,5,7);
M(randi(numel(M),1,9)) = NaN
M = 5×7
1 NaN 1 1 2 3 1 NaN 1 2 NaN 1 1 3 NaN 3 NaN 1 2 1 NaN 2 NaN 3 2 3 2 2 1 1 2 NaN 1 3 2
V = median(M,1,'omitnan')
V = 1×7
1 1 2 1 2 2 2
X = isnan(M);
M(X) = repelem(V,sum(X,1))
M = 5×7
1 1 1 1 2 3 1 1 1 2 1 1 1 3 1 3 2 1 2 1 2 2 1 3 2 3 2 2 1 1 2 1 1 3 2

Yazan
Yazan 2021 年 8 月 10 日
clc, clear
x1 = randn(5, 5);
x1(randi(numel(x1), 1, 5)) = nan;
x2 = fillmissing(x1, 'movmedian', size(x1,1)*2, 1);
display(x1)
x1 = 5×5
NaN 0.1826 NaN 0.3875 -0.7928 1.3983 -0.1527 0.1261 0.1482 -0.8491 1.4623 0.7005 -0.0511 -0.1259 1.1562 0.8948 0.0311 0.0064 NaN NaN -0.2615 -0.1371 -1.7245 0.9723 0.5918
display(x2)
x2 = 5×5
1.1466 0.1826 -0.0223 0.3875 -0.7928 1.3983 -0.1527 0.1261 0.1482 -0.8491 1.4623 0.7005 -0.0511 -0.1259 1.1562 0.8948 0.0311 0.0064 0.2678 -0.1005 -0.2615 -0.1371 -1.7245 0.9723 0.5918

カテゴリ

Help Center および File ExchangePreprocessing Data についてさらに検索

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by