speech to text conversion

am getting a dimension mismatch error in this code as: Error in ==> lpc_training1 at 57.cud sum1 pls help correct it? fw(i,:) = a;

Fs = 10000; % Sampling Frequency (Hz) n = 12; % LPC order Nseconds = 1; % Length of speech signal

% List of words (you can add more words to this list but make sure
% each word has five characters (if less then pad it with spaces)
words = ['   up';
         ' down';
         ' left';
         'right'];

% Matrix to store features for each word (rows correspond to words)
%fw = zeros(size(words,1),n);

fprintf('You will get one second to say each word.\n\n');

% For each word, get the word from microphone and compute its features
for i=1:size(words,1)
    fprintf('Hit enter and say immediately ''%s'':',words(i,:));
    % pause for enter key
    junk=input('');

      % get a word from microphone
      x  = wavrecord(Nseconds*Fs, Fs, 'double');

      % Calculate the features of the word
     % f = lpc_feature(y,n);
      % x: Speech signal
  M = n; % M: Order of LPC model
  seg = 240; % Segment or frame size
  if (size(x,2) == 1)
  x = x'; 
  end
  npts = length(x);
  nseg = floor(npts/seg); % nseg: Number of segments in the signal
  % Perform the following for each and every segment of the speech
  for each = 1:nseg
  xx = x((each - 1)*seg + [1:seg]);
  [a,G] = lpc(xx, M);
  e = filter(a,1,xx); % Computer residual error signal
  G = sqrt(G);
  e = e/G;
  % Save lpc parameter, gain and redidual errors

%parameter(each,:) = a;
gain(each) = G;
residu((each - 1)*seg + [1:seg]) = e;
end
%[residu,Q] = quantization(residu,16);

      % Save them in the features matrix
      fw(i,:) = a;
      %     abs(f)
      %     plot(1:Fs,fft(y));
  end

% Save features matrix to a file (this file will be loaded into Matlab during speech recognition)
save words_lpc.mat Fs n words fw;