Matlab。用平均值替换缺失的值

问题

如何用string（最常见的类）和number列的平均值替换缺少的列值

数据示例取自：

例如，将

NaN

替换为“Iris setosa”

我有代码

它只替换值，但也替换字符串

function dataWithReplaced = replaceNaNWithAvg(data)

dataWithReplaced = [ ];

averagePerCol = table2array(varfun(@nanmean, data(: , 1:4)));

for i = 1:4

    dataColumn = table2array(data( : , i));
    dataColumn(isnan(dataColumn)) = averagePerCol(1, i);

    dataWithReplaced = [dataWithReplaced dataColumn];

end

end

---

我是MATlab新手，所以很多事情对我来说并不明显。

以下解决方案解决了这个问题：

• 将最后一个表列转换为单元格数组（需要单元格数组来容纳不同长度的字符串）
• （NaN元素打断了下一节）
• 在stringColumn中查找NaN元素的所有索引（基于上一节，我使用了

  cellfun

  ）
• R用最常用的字符串替换索引中的元素

由于您是Matlab新手，我的解决方案对您来说将非常复杂（对我来说它看起来很复杂）。
可能有一个更简单的解决方案，我找不到

请参阅以下代码示例：

%Create data table for the example.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
VarName1 = [4.9; 7.3; 6.7; 7.2; 6.5; 6.4; 6.8; 5.7; 5.8; 6.4; 6.5];
VarName2 = [2.5; 2.9; 2.5; 3.6; 3.2; 2.7; 3.0; 2.5; 2.8; 3.2; 3.0];
VarName3 = [4.5; 6.3; 5.8; 6.1; 5.1; 5.3; 5.5; 5.0; 5.1; 5.3; 5.5];
VarName4 = [1.7; 1.8; 1.8; 2.5; 2.0; 1.9; 2.1; 2.0; 2.4; 2.3; 1.8];
VarName5 = {NaN; 'aa'; 'aa'; 'bbb'; NaN; 'ccc'; 'ccc'; 'ccc'; 'ccc'; 'dddd'; 'dddd'};
data = table(VarName1, VarName2, VarName3, VarName4, VarName5);
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%Convert last table column to cell array.
stringColumn = table2cell(data(:, 5));

%Remove all NaN elements from cell array
%Reference: https://www.mathworks.com/matlabcentral/newsreader/view_thread/314852
x = stringColumn(cell2mat(cellfun(@ischar,stringColumn,'UniformOutput',0)));

%Find most repeated string in cell array:
%Reference: https://www.mathworks.com/matlabcentral/answers/7973-how-to-find-out-which-item-is-mode-of-cell-array
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
y = unique(x);
n = zeros(length(y), 1);
for iy = 1:length(y)
    n(iy) = length(find(strcmp(y{iy}, x)));
end
[~, itemp] = max(n);
commonStr = y(itemp);
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

%Find all indeces of NaN elements in stringColumn.
nanIdx = find(cell2mat(cellfun(@ischar,stringColumn,'UniformOutput',0)) == 0);

%Rplace elements with NaN values with commonStr.
stringColumn(nanIdx) = commonStr;

%Replace last column of original table
data(:, 5) = stringColumn;

---

非常感谢。我明白了。我在MATlab方面是新手，但在编码方面不是。）