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LAPACK
3.4.1
LAPACK: Linear Algebra PACKage
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00001 *> \brief \b DGET06 00002 * 00003 * =========== DOCUMENTATION =========== 00004 * 00005 * Online html documentation available at 00006 * http://www.netlib.org/lapack/explore-html/ 00007 * 00008 * Definition: 00009 * =========== 00010 * 00011 * DOUBLE PRECISION FUNCTION DGET06( RCOND, RCONDC ) 00012 * 00013 * .. Scalar Arguments .. 00014 * DOUBLE PRECISION RCOND, RCONDC 00015 * .. 00016 * 00017 * 00018 *> \par Purpose: 00019 * ============= 00020 *> 00021 *> \verbatim 00022 *> 00023 *> DGET06 computes a test ratio to compare two values for RCOND. 00024 *> \endverbatim 00025 * 00026 * Arguments: 00027 * ========== 00028 * 00029 *> \param[in] RCOND 00030 *> \verbatim 00031 *> RCOND is DOUBLE PRECISION 00032 *> The estimate of the reciprocal of the condition number of A, 00033 *> as computed by DGECON. 00034 *> \endverbatim 00035 *> 00036 *> \param[in] RCONDC 00037 *> \verbatim 00038 *> RCONDC is DOUBLE PRECISION 00039 *> The reciprocal of the condition number of A, computed as 00040 *> ( 1/norm(A) ) / norm(inv(A)). 00041 *> \endverbatim 00042 * 00043 * Authors: 00044 * ======== 00045 * 00046 *> \author Univ. of Tennessee 00047 *> \author Univ. of California Berkeley 00048 *> \author Univ. of Colorado Denver 00049 *> \author NAG Ltd. 00050 * 00051 *> \date November 2011 00052 * 00053 *> \ingroup double_lin 00054 * 00055 * ===================================================================== 00056 DOUBLE PRECISION FUNCTION DGET06( RCOND, RCONDC ) 00057 * 00058 * -- LAPACK test routine (version 3.4.0) -- 00059 * -- LAPACK is a software package provided by Univ. of Tennessee, -- 00060 * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- 00061 * November 2011 00062 * 00063 * .. Scalar Arguments .. 00064 DOUBLE PRECISION RCOND, RCONDC 00065 * .. 00066 * 00067 * ===================================================================== 00068 * 00069 * .. Parameters .. 00070 DOUBLE PRECISION ZERO, ONE 00071 PARAMETER ( ZERO = 0.0D+0, ONE = 1.0D+0 ) 00072 * .. 00073 * .. Local Scalars .. 00074 DOUBLE PRECISION EPS, RAT 00075 * .. 00076 * .. External Functions .. 00077 DOUBLE PRECISION DLAMCH 00078 EXTERNAL DLAMCH 00079 * .. 00080 * .. Intrinsic Functions .. 00081 INTRINSIC MAX, MIN 00082 * .. 00083 * .. Executable Statements .. 00084 * 00085 EPS = DLAMCH( 'Epsilon' ) 00086 IF( RCOND.GT.ZERO ) THEN 00087 IF( RCONDC.GT.ZERO ) THEN 00088 RAT = MAX( RCOND, RCONDC ) / MIN( RCOND, RCONDC ) - 00089 $ ( ONE-EPS ) 00090 ELSE 00091 RAT = RCOND / EPS 00092 END IF 00093 ELSE 00094 IF( RCONDC.GT.ZERO ) THEN 00095 RAT = RCONDC / EPS 00096 ELSE 00097 RAT = ZERO 00098 END IF 00099 END IF 00100 DGET06 = RAT 00101 RETURN 00102 * 00103 * End of DGET06 00104 * 00105 END