mrmr算法，程序运行时出现此错误：函数或变量 't' 无法识别

function [fea] = mrmr_mid_d(d, f, K)

% function [fea] = mrmr_mid_d(d, f, K)

%

% MID scheme according to MRMR

% d-输入N*M矩阵，N个采样值，M个特征，特征向量

% f-输入的N*1向量，分类结果

% K-选择的特征的个数

data=importdata('Iris.data');

d=data(:,1:end-1);

f=data(:,end);

K=3;

bdisp=0;

nd = size(d,2);

nc = size(d,1);

t1=cputime;

for i=1:nd

t(i) = mutualinfo(d(:,i), f);

end

fprintf('calculate the marginal dmi costs %5.1fs.\n', cputime-t1);

[tmp, idxs] = sort(-t);

fea_base = idxs(1:K);