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Tests for the ScaLAPACK GSEP routines

Finding the eigenvalues and eigenvectors of symmetric matrices A and B, where B is also positive definite, follows the same stages as the symmetric eigenvalue problem except that the problem is first reduced from generalized to standard form using PxSYGST/PxHEGST.

To check these calculations, the following test ratios are computed:

$\displaystyle r_1$ $\textstyle =$ $\displaystyle \frac{ \left\Vert A \, Z - B \, Z \, D \right\Vert}
{ \left\Vert A\right\Vert\, \left\Vert Z \right\Vert\, n \, ulp}$  
    $\displaystyle \mbox{calling PxSYGVX/PxHEGVX with ITYPE=1 and UPLO='U'}$  
$\displaystyle r_2$ $\textstyle =$ $\displaystyle \frac{ \left\Vert A \, Z - B \, Z \, D \right\Vert}
{ \left\Vert A\right\Vert\, \left\Vert Z \right\Vert\, n \, ulp}$  
    $\displaystyle \mbox{calling PxSYGVX/PxHEGVX with ITYPE=1 and UPLO='L'}$  
$\displaystyle r_5$ $\textstyle =$ $\displaystyle \frac{ \left\Vert A \, Z - B \, Z \, D \right\Vert}
{ \left\Vert A\right\Vert\, \left\Vert Z \right\Vert\, n \, ulp}$  
    $\displaystyle \mbox{calling PxSYGVX/PxHEEVX with ITYPE=2 and UPLO='U'}$  
$\displaystyle r_8$ $\textstyle =$ $\displaystyle \frac{ \left\Vert A \, B \, Z - Z \, D \right\Vert}
{ \left\Vert A\right\Vert\, \left\Vert Z \right\Vert\, n \, ulp}$  
    $\displaystyle \mbox{calling PxSYGVX/PxHEEVX with ITYPE=2 and UPLO='L'}$  
$\displaystyle r_{10}$ $\textstyle =$ $\displaystyle \frac{ \left\Vert A \, B \, Z - Z \, D \right\Vert}
{ \left\Vert A\right\Vert\, \left\Vert Z \right\Vert\, n \, ulp}$  
    $\displaystyle \mbox{calling PxSYGVX/PxHEEVX with ITYPE=3 and UPLO='U'}$  
$\displaystyle r_{12}$ $\textstyle =$ $\displaystyle \frac{ \left\Vert B \, A \, Z - Z \, D \right\Vert}
{ \left\Vert A\right\Vert\, \left\Vert Z \right\Vert\, n \, ulp}$  
    $\displaystyle \mbox{calling PxSYGVX/PxHEEVX with ITYPE=3 and UPLO='L'}$  
$\displaystyle r_{14}$ $\textstyle =$ $\displaystyle \frac{ \left\Vert B \, A \, Z - Z \, D \right\Vert}
{ \left\Vert A\right\Vert\, \left\Vert Z \right\Vert\, n \, ulp}$  



Subsections
next up previous contents
Next: Input File for Testing Up: More About the ScaLAPACK Previous: Input File for Testing   Contents
Susan Blackford 2001-08-12