DGET32
Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
November 2006
November 2006
Purpose
DGET32 tests DLASY2, a routine for solving
op(TL)*X + ISGN*X*op(TR) = SCALE*B
where TL is N1 by N1, TR is N2 by N2, and N1,N2 =1 or 2 only.
X and B are N1 by N2, op() is an optional transpose, an
ISGN = 1 or -1. SCALE is chosen less than or equal to 1 to
avoid overflow in X.
The test condition is that the scaled residual
norm( op(TL)*X + ISGN*X*op(TR) = SCALE*B )
/ ( max( ulp*norm(TL), ulp*norm(TR)) * norm(X), SMLNUM )
should be on the order of 1. Here, ulp is the machine precision.
Also, it is verified that SCALE is less than or equal to 1, and
that XNORM = infinity-norm(X).
op(TL)*X + ISGN*X*op(TR) = SCALE*B
where TL is N1 by N1, TR is N2 by N2, and N1,N2 =1 or 2 only.
X and B are N1 by N2, op() is an optional transpose, an
ISGN = 1 or -1. SCALE is chosen less than or equal to 1 to
avoid overflow in X.
The test condition is that the scaled residual
norm( op(TL)*X + ISGN*X*op(TR) = SCALE*B )
/ ( max( ulp*norm(TL), ulp*norm(TR)) * norm(X), SMLNUM )
should be on the order of 1. Here, ulp is the machine precision.
Also, it is verified that SCALE is less than or equal to 1, and
that XNORM = infinity-norm(X).
Arguments
| RMAX |
(output) DOUBLE PRECISION
Value of the largest test ratio.
|
| LMAX |
(output) INTEGER
Example number where largest test ratio achieved.
|
| NINFO |
(output) INTEGER
Number of examples returned with INFO.NE.0.
|
| KNT |
(output) INTEGER
Total number of examples tested.
|