last N-IHI rows of B is zero.
          If JOB = 'N', the arrays A and B are not referenced.

  LDB    INTEGER
          The leading dimension of the array B.  LDB &gt;= MAX(1, N).

  ILO     (output) INTEGER
  IHI     (output) INTEGER
          ILO and IHI are set to integers such that on exit
          A(i,j) = 0 and B(i,j) = 0 if i &gt; j and
          j = 1,...,ILO-1 or i = IHI+1,...,N.
          If JOB = 'N' or 'S', ILO = 1 and IHI = N.

  LSCALE  (output) DOUBLE PRECISION array, dimension (N)
        