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Tests for the ScaLAPACK NEP routines

The PxLAHQR test program generates random upper Hessenberg matrices, completes a Schur decomposition on them, and then tests the resulting Schur decomposition for maintaining similarity. The following tests will be performed on P_LAHQR:

$\displaystyle r_1$ $\textstyle =$ $\displaystyle \frac{\left\Vert H - Q S Q^T \right\Vert}
{n \, ulp \, \left\Vert H \right\Vert}$  
$\displaystyle r_2$ $\textstyle =$ $\displaystyle \frac{\left\Vert I - Q^T Q \right\Vert}
{n \, ulp }$  

where $Q$ is the Schur vectors of the upper Hessenberg matrix $H$ when the Schur vector and Schur decomposition option is given. $N$ is the order of the matrix, $ulp$ represents PxLAMCH( ICTXT, 'P' ), and the one-norm is used for the norm computations.


Susan Blackford 2001-08-12