code: public static void extractHouseholderRow( ZMatrixRMaj A ,
                                                int row ,
                                                int col0, int col1 , double u[], int offsetU )
      {
          int indexU = (offsetU+col0)*2;
          u[indexU]   = 1;
          u[indexU+1] = 0;
  
          int indexA = (row*A.numCols + (col0+1))*2;
          System.arraycopy(A.data,indexA,u,indexU+2,(col1-col0-1)*2);
      }
docs: Extracts a house holder vector from the rows of A and stores it in u
  @param A Complex matrix with householder vectors stored in the upper right triangle
  @param row Row in A
  @param col0 first row in A (implicitly assumed to be r + i0)
  @param col1 last row +1 in A
  @param u Output array storage
  @param offsetU first index in U