求大神解答，matlab程序运行出错

关于SRC算法的
function [result2, relative_error2] = src(trn,tst, solver)
repeat = 1;
for r = 1:repeat
% Normalising the training set
for i=1:size(trn.X,2)
Atilde(:,i)=trn.X(:,i)/norm(trn.X(:,i),2);
end
n = size(trn.X,2); % total number of samples in the training database
k = max(trn.y); % number of classes
onesvecs = full(ind2vec(trn.y)); % preparing classification target
n_test = size(tst.X,2); % number of test data to be classified
if strcmp(solver, 'omp')
param.L = 9; % parameter for Sparse Solver
param.eps=0.1;
end
if strcmp(solver, 'apg')
param.regul='l1'; % parameter for Sparse Solver
param.loss='square';
beta0=zeros(size(Atilde,2),1);
param.lambda = 0.07;
end
% start classifcation
for iter = 1:n_test % looping through all the test samples
ytilde = tst.X(:,iter);
ytilde = ytilde/norm(ytilde); % normalizing the test sample
if strcmp(solver, 'omp'); xp = mexOMP(ytilde,Atilde,param);end
if strcmp(solver, 'apg'); xp =mexFistaFlat(ytilde,Atilde,beta0,param);end
% decision making
for i=1:k
deltavec(:,i) = onesvecs(i,:)'.* xp;
residual2(r,iter,i) = norm(ytilde-Atilde*deltavec(:,i));
end
[B,IX] = sort(residual2);
result(iter) = IX(1);
end
end
res2 = sum(residual2,1);
for iter = 1:n_test
[B, Ind] = sort(res2(1,iter,:));
result2(iter) = Ind(1);
end
% finding the relative classification error
relative_error2 = size(find(abs(tst.y-result2)),2)/size(tst.y,2);