code: public void inverse(float data[], int rowspan) {
      backtransform(data, rowspan); 
      float norm = normalization();
      for(int i=0; i<nrows; i++){
        for(int j=0; j<ncols; j++){
  	data[i*rowspan + 2*j]   *= norm; 
  	data[i*rowspan + 2*j+1] *= norm; }}}
docs: Compute the (nomalized) inverse FFT of data, leaving it in place.