function [U, S, V, P,P_res, L,L_res] = cca_fun_static(X,Y) % CCA calculate canonical correlations % % [U, S, V, P, L] = cca(Y_tr,U_tr) where P and L contains the canonical correlation % matrices as columns and S is a matrix with corresponding canonical % correlations. The correlations are sorted in descending order. Y_tr and % U_tr are matrices where each column is a sample. Hence, Y_tr and U_tr must have % the same number of columns. % % Example: If Y is M*K and U_tr is L*K there are rank=MIN(M,L) solutions. U is % then M*M, V is L*L and S is M*L. P is M*rank, L is L*rank. % % % ? 2014 Zhiwen Chen, Duisburg-Essen universitet % --- Calculate covariance matrices --- [l,n_s]=size(Y); [m,~]=size(X); %% %CVA decomposition [U,S,V]=svd((X*X')^(-0.5)*(X*Y')*(Y*Y')^(-0.5)); %%%%%%%%%%%%%%%%%%%%%%%% Determine the order n_o = rank(S); S = S(1:n_o,1:n_o); % for i=1:size(S,2) % if sum(sum(S(1:i,1:i)))/sum(sum(S))>0.8 % n_o=i; % break % end % end %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Get L,P,X,Q,Omega,X P=(X*X')^(-0.5)*U(:,1:n_o); P_res = (X*X')^(-0.5)*U(:,n_o+1:end); L=(Y*Y')^(-0.5)*V(:,1:n_o); L_res=(Y*Y')^(-0.5)*V(:,n_o+1:end); end
时间: 2024-04-03 07:32:12 浏览: 13
这段代码实现了CCA(Canonical Correlation Analysis,典型相关分析)算法。该算法可以用于分析两个不同数据集之间的相关性,并找到它们之间的线性关系。该算法的输入是两个矩阵X和Y,它们分别表示两个数据集,每一列为一个样本,X的大小为m*n_s,Y的大小为l*n_s。其中,m和l分别为两个数据集的维数,n_s为样本数量。输出是四个矩阵U、S、V和P,以及两个残差矩阵P_res和L_res。
算法的主要步骤如下:
1. 计算两个数据集的协方差矩阵;
2. 对协方差矩阵进行SVD分解;
3. 根据SVD分解的结果,计算出CCA的解;
4. 求解P、L和残差矩阵P_res和L_res。
其中,U、S和V分别表示SVD分解得到的左奇异矩阵、奇异值矩阵和右奇异矩阵,P和L表示两个数据集之间的映射矩阵,P_res和L_res表示P和L的残差矩阵。最后返回这些矩阵作为函数的输出。
相关问题
p=gen_encode(X,Nb,1,u)
As an AI language model, I cannot provide a specific answer without knowing the context of the code and the values of the variables used. However, I can provide an explanation of the function and its parameters.
The function "gen_encode" is likely a custom function defined in the code. Its purpose is to encode a given input "X" using a specific algorithm, which is not clear from the provided code snippet. The encoded output is stored in "p".
The parameters of the function are:
- X: the input data to be encoded.
- Nb: the number of bits to be used for encoding.
- 1: a constant value used by the encoding algorithm, whose purpose is unknown from the code snippet.
- u: a variable used by the encoding algorithm, whose purpose is unknown from the code snippet.
具体分析程序:function [U, S, V, P,P_res, L,L_res] = cca_fun_static(X,Y) % CCA calculate canonical correlations % % [U, S, V, P, L] = cca(Y_tr,U_tr) where P and L contains the canonical correlation % matrices as columns and S is a matrix with corresponding canonical % correlations. The correlations are sorted in descending order. Y_tr and % U_tr are matrices where each column is a sample. Hence, Y_tr and U_tr must have % the same number of columns. % % Example: If Y is M*K and U_tr is L*K there are rank=MIN(M,L) solutions. U is % then M*M, V is L*L and S is M*L. P is M*rank, L is L*rank. % % % ? 2014 Zhiwen Chen, Duisburg-Essen universitet % --- Calculate covariance matrices --- [l,n_s]=size(Y); [m,~]=size(X); %% %CVA decomposition [U,S,V]=svd((X*X')^(-0.5)*(X*Y')*(Y*Y')^(-0.5)); %%%%%%%%%%%%%%%%%%%%%%%% Determine the order n_o = rank(S); S = S(1:n_o,1:n_o); % for i=1:size(S,2) % if sum(sum(S(1:i,1:i)))/sum(sum(S))>0.8 % n_o=i; % break % end % end %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% Get L,P,X,Q,Omega,X P=(X*X')^(-0.5)*U(:,1:n_o); P_res = (X*X')^(-0.5)*U(:,n_o+1:end); L=(Y*Y')^(-0.5)*V(:,1:n_o); L_res=(Y*Y')^(-0.5)*V(:,n_o+1:end); end
这段程序是一个静态的CCA(Canonical Correlation Analysis,典型相关分析)算法实现。CCA是一种多变量数据分析方法,它尝试找到两个数据集中相关性最强的线性组合。这个程序输入两个数据矩阵X和Y,然后输出它们的CCA结果。具体来说,它输出了两个数据集的主成分矩阵(即P和L),以及它们的主成分之间的相关系数矩阵(即S)。
这个程序的具体实现过程是:
1. 首先,计算X和Y的协方差矩阵。
2. 然后,对协方差矩阵进行奇异值分解(SVD)。
3. 取前n_o个奇异值,并将它们组成一个对角矩阵S。
4. 根据SVD的结果,计算X和Y的主成分矩阵P和L。
5. 最后,计算主成分之间的相关系数矩阵。
需要注意的是,这个程序中的rank函数应该是指SVD的秩,而不是矩阵的秩。程序中的Determine the order这一部分被注释掉了,因此n_o的值是取前n_o个奇异值的数量,而不是根据阈值计算得到的。