改进熵值法matlab代码
时间: 2023-06-24 12:09:03 浏览: 101
以下是改进熵值法的MATLAB代码,其中包括了对输入数据和权重矩阵的检查:
```matlab
function [score, rank] = improved_entropy(data, weight)
% Check if data and weight have the same number of rows
if size(data,1) ~= size(weight,1)
error('Data and weight matrices must have the same number of rows');
end
% Check if weight matrix is normalized
if sum(weight,2) ~= 1
error('Weight matrix rows must sum to 1');
end
% Calculate normalized data matrix
normalized_data = zeros(size(data));
for i = 1:size(data,2)
col = data(:,i);
normalized_col = (col - min(col)) / (max(col) - min(col));
normalized_data(:,i) = normalized_col;
end
% Calculate entropy of each attribute
attribute_entropies = zeros(1,size(normalized_data,2));
for i = 1:size(normalized_data,2)
col = normalized_data(:,i);
p = col / sum(col);
attribute_entropies(i) = -sum(p .* log2(p));
end
% Calculate entropy reduction of each attribute
entropy_reduction = zeros(1,size(normalized_data,2));
for i = 1:size(normalized_data,2)
col = normalized_data(:,i);
p = col / sum(col);
reduced_p = p.^weight(i);
reduced_p = reduced_p / sum(reduced_p);
entropy_reduction(i) = attribute_entropies(i) - sum(reduced_p .* log2(reduced_p));
end
% Calculate score for each attribute
score = entropy_reduction / sum(entropy_reduction);
% Sort attributes by score in descending order
[rank,~] = sort(score,'descend');
end
```
在使用该函数时,需要提供一个数据矩阵和一个权重矩阵。数据矩阵应该是一个 $n \times m$ 的矩阵,其中 $n$ 是样本数量,$m$ 是属性数量。权重矩阵应该是一个 $m \times 1$ 的矩阵,其中每个元素都是一个介于 0 和 1 之间的数,表示对应属性的重要性。
函数将返回每个属性的得分和按得分降序排列的属性排名。
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