 but no error message related to LZWORK is issued
          by XERBLA.
          If LDWORK = 0 and LZWORK = 0 are both set on entry, then
          on exit, INFO = -30, but both DWORK(1) and ZWORK(1) are
          set the minimum values of LDWORK and LZWORK, respectively.

  LZWORK  INTEGER
          The dimension of the array ZWORK.
          LZWORK &gt;= 1,  if MIN(N,M,P) = 0, or B = 0, or C = 0;
          LZWORK &gt;= MAX(1, (N+M)*(N+P) + 2*MIN(M,P) + MAX(M,P)),
                        otherwise.
       