 array Q.  LDQ2 &gt;= 1,
          and, if COMPQ &lt;&gt; 'N', LDQ2 &gt;= MAX(1,N).

  ALPHAR  (output) DOUBLE PRECISION array, dimension (N)
          On exit, if INFO = 0, the leading N elements of this array
          contain the scaled real parts of the eigenvalues of the
          matrix product A. The i-th eigenvalue of A is given by

          (ALPHAR(I) + ALPHAI(I)*SQRT(-1))/BETA(I) * BASE**SCAL(I),

          where BASE is the machine base (often 2.0). Complex
          conjugate eigenvalues appear