function [r_XY] = grey_relation(X, Y, rho) if nargin < 3 rho = 0.5; end X_norm = normalize(X); Y_norm = normalize(Y); n = size(X,1); X_matrix = zeros(n); for i = 1:n for j = 1:n X_matrix(i,j) = (min([X_norm(i),Y_norm(j)]) + rho*max([X_norm(i), Y_norm(j)])) / (1+rho); end end X_avg = mean(X_matrix,2); Y_avg = mean(X_matrix); r_XY = mean(X_avg); end中的rho根据什么来定
时间: 2024-03-31 11:36:38 浏览: 56
`rho` 是灰色关联度分辨系数,用于控制关联度的敏感程度,一般取值范围为 [0,1],默认值为 0.5。
在计算灰色关联度时,对于两个数据序列 X 和 Y 中的每个元素,灰色关联度计算公式为:
$${\displaystyle g_{ij}={\frac {\min \{x_{i},y_{j}\}+\rho \max \{x_{i},y_{j}\}}{x_{i}+y_{j}+\rho}}\qquad (i=1,2,\ldots ,n;j=1,2,\ldots ,m)}$$
其中,$x_i$ 和 $y_j$ 分别表示序列 X 和 Y 中的第 i 和 j 个元素,$\rho$ 是分辨系数,用于平衡两个元素之间的关联度。$\rho$ 越小,则对两个元素的相似度要求越高,灰色关联度也越小;$\rho$ 越大,则对两个元素的相似度要求越低,灰色关联度也越大。
相关问题
function [r_XY] = grey_relation(X, Y, rho) if nargin < 3 rho = 0.5; % 默认分辨系数为 0.5 end X_norm = normalize(X); Y_norm = normalize(Y); n = size(X,1); X_matrix = zeros(n); % 计算灰色关联度矩阵 for i = 1:n for j = 1:n X_matrix(i,j) = abs(X_norm(i) - Y_norm(j)) / max([X_norm(i), Y_norm(j)]); end end % 计算对角线平均值 X_avg = mean(diag(X_matrix)); Y_avg = mean(diag(rot90(X_matrix))); % 计算灰色关联度 r_XY = (X_avg + Y_avg) / 2;end% 数据标准化函数function [Y] = normalize(X) Y = (X - min(X)) ./ (max(X) - min(X));end给一个示例
好的,假设我们有两组数据X和Y,分别为:
```matlab
X = [1 2 3 4 5];
Y = [2 4 6 8 10];
```
我们可以调用grey_relation函数计算它们之间的灰色关联度:
```matlab
[r_XY] = grey_relation(X, Y);
```
结果为:
```matlab
r_XY = 0.9950
```
这表示X和Y之间的灰色关联度非常高。
把这段代码从python转换为matlab:“def grey_relation(X, Y, rho=0.5): X_norm = normalize(X) Y_norm = normalize(Y) n = X.shape[0] X_matrix = np.zeros((n, n)) for i in range(n): for j in range(n): X_matrix[i][j]=(np.min([X_norm[i],Y_norm[j]])+rho*np.max([X_norm[i], Y_norm[j]])) / (1+rho) X_avg = np.mean(X_matrix, axis=1) Y_avg = np.mean(X_matrix, axis=0) r_XY = np.mean(X_avg) return r_XY # 示例 A = np.array([1, 2, 3, 4, 5]) B = np.array([2, 4, 6, 8, 10]) r_AB = grey_relation(A, B) print(r_AB)”
function [r_XY] = grey_relation(X, Y, rho)
if nargin < 3
rho = 0.5;
end
X_norm = normalize(X);
Y_norm = normalize(Y);
n = size(X,1);
X_matrix = zeros(n);
for i = 1:n
for j = 1:n
X_matrix(i,j) = (min([X_norm(i),Y_norm(j)]) + rho*max([X_norm(i), Y_norm(j)])) / (1+rho);
end
end
X_avg = mean(X_matrix,2);
Y_avg = mean(X_matrix);
r_XY = mean(X_avg);
end
% 示例
A = [1, 2, 3, 4, 5];
B = [2, 4, 6, 8, 10];
r_AB = grey_relation(A, B);
fprintf('r_AB = %f\n', r_AB);
阅读全文