% RFFT: scaled real FFT, X=rfft(x)
% Returns the positive-frequency half of the transform X=FFT(x).
% The transform X is normalized so that if {x} is a sine wave of
% unit amplitude and frequency n*df, then X[n]=1.
% Usage:    X=rfft(x)
% If x is N points long, NF=N/2+1 complex points are returned.
% See also IRFFT, FAST, FSST, FFT, IFFT,

function X=rfft(x)
  [m,n]=size(x);
  if (m==1 | n==1)
    % original...
    N=length(x)/2+1;
    xc=fft(x);
    X=xc(1:fix(N));
  else
    % do it column-wise...
    N=m/2+1;
    xc=fft(x);
    X=xc(1:fix(N),:);
  end

  X = X / (length(x)/2);
  return