 L &lt; N.

  A       (input/output) DOUBLE PRECISION array, dimension (LDA,N)
          On entry, the leading N-by-N part of this array must
          contain the upper quasi-triangular matrix A whose
          selected 2-by-2 diagonal block is to be processed.
          On exit, the leading N-by-N part of this array contains
          the upper quasi-triangular matrix A after its selected
          block has been splitt and/or put in the LAPACK standard
          form.

  LDA     INTEGER
          The lea