How can I take first element in the first cell of my_list in matlab and give it to perceptron to train the data ?

for lineID=1:length
  tline = fopen(fid);
  C = strsplit(tline, ' ');
  lq_list{lineID} = C{1};
end
for lq_list=1:sizeof(lq_list);

    M = strsplit(C{1}, ':');
    my_list{lq_list}= M{1};
end
for my_list = 1:sizeof(my_list) ;
  if(  )