MAGMA  1.2.0
MatrixAlgebraonGPUandMulticoreArchitectures
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Macros Groups
sget06.f
Go to the documentation of this file.
1  REAL FUNCTION sget06( RCOND, RCONDC )
2 *
3 * -- LAPACK test routine (version 3.1) --
4 * Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd..
5 * November 2006
6 *
7 * .. Scalar Arguments ..
8  REAL rcond, rcondc
9 * ..
10 *
11 * Purpose
12 * =======
13 *
14 * SGET06 computes a test ratio to compare two values for RCOND.
15 *
16 * Arguments
17 * ==========
18 *
19 * RCOND (input) REAL
20 * The estimate of the reciprocal of the condition number of A,
21 * as computed by SGECON.
22 *
23 * RCONDC (input) REAL
24 * The reciprocal of the condition number of A, computed as
25 * ( 1/norm(A) ) / norm(inv(A)).
26 *
27 * =====================================================================
28 *
29 * .. Parameters ..
30  REAL zero, one
31  parameter( zero = 0.0e+0, one = 1.0e+0 )
32 * ..
33 * .. Local Scalars ..
34  REAL eps, rat
35 * ..
36 * .. External Functions ..
37  REAL slamch
38  EXTERNAL slamch
39 * ..
40 * .. Intrinsic Functions ..
41  INTRINSIC max, min
42 * ..
43 * .. Executable Statements ..
44 *
45  eps = slamch( 'Epsilon' )
46  IF( rcond.GT.zero ) THEN
47  IF( rcondc.GT.zero ) THEN
48  rat = max( rcond, rcondc ) / min( rcond, rcondc ) -
49  $ ( one-eps )
50  ELSE
51  rat = rcond / eps
52  END IF
53  ELSE
54  IF( rcondc.GT.zero ) THEN
55  rat = rcondc / eps
56  ELSE
57  rat = zero
58  END IF
59  END IF
60  sget06 = rat
61  return
62 *
63 * End of SGET06
64 *
65  END