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LAPACK
3.4.1
LAPACK: Linear Algebra PACKage
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00001 *> \brief \b ZLAT2C 00002 * 00003 * =========== DOCUMENTATION =========== 00004 * 00005 * Online html documentation available at 00006 * http://www.netlib.org/lapack/explore-html/ 00007 * 00008 *> \htmlonly 00009 *> Download ZLAT2C + dependencies 00010 *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/zlat2c.f"> 00011 *> [TGZ]</a> 00012 *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/zlat2c.f"> 00013 *> [ZIP]</a> 00014 *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/zlat2c.f"> 00015 *> [TXT]</a> 00016 *> \endhtmlonly 00017 * 00018 * Definition: 00019 * =========== 00020 * 00021 * SUBROUTINE ZLAT2C( UPLO, N, A, LDA, SA, LDSA, INFO ) 00022 * 00023 * .. Scalar Arguments .. 00024 * CHARACTER UPLO 00025 * INTEGER INFO, LDA, LDSA, N 00026 * .. 00027 * .. Array Arguments .. 00028 * COMPLEX SA( LDSA, * ) 00029 * COMPLEX*16 A( LDA, * ) 00030 * .. 00031 * 00032 * 00033 *> \par Purpose: 00034 * ============= 00035 *> 00036 *> \verbatim 00037 *> 00038 *> ZLAT2C converts a COMPLEX*16 triangular matrix, SA, to a COMPLEX 00039 *> triangular matrix, A. 00040 *> 00041 *> RMAX is the overflow for the SINGLE PRECISION arithmetic 00042 *> ZLAT2C checks that all the entries of A are between -RMAX and 00043 *> RMAX. If not the convertion is aborted and a flag is raised. 00044 *> 00045 *> This is an auxiliary routine so there is no argument checking. 00046 *> \endverbatim 00047 * 00048 * Arguments: 00049 * ========== 00050 * 00051 *> \param[in] UPLO 00052 *> \verbatim 00053 *> UPLO is CHARACTER*1 00054 *> = 'U': A is upper triangular; 00055 *> = 'L': A is lower triangular. 00056 *> \endverbatim 00057 *> 00058 *> \param[in] N 00059 *> \verbatim 00060 *> N is INTEGER 00061 *> The number of rows and columns of the matrix A. N >= 0. 00062 *> \endverbatim 00063 *> 00064 *> \param[in] A 00065 *> \verbatim 00066 *> A is COMPLEX*16 array, dimension (LDA,N) 00067 *> On entry, the N-by-N triangular coefficient matrix A. 00068 *> \endverbatim 00069 *> 00070 *> \param[in] LDA 00071 *> \verbatim 00072 *> LDA is INTEGER 00073 *> The leading dimension of the array A. LDA >= max(1,N). 00074 *> \endverbatim 00075 *> 00076 *> \param[out] SA 00077 *> \verbatim 00078 *> SA is COMPLEX array, dimension (LDSA,N) 00079 *> Only the UPLO part of SA is referenced. On exit, if INFO=0, 00080 *> the N-by-N coefficient matrix SA; if INFO>0, the content of 00081 *> the UPLO part of SA is unspecified. 00082 *> \endverbatim 00083 *> 00084 *> \param[in] LDSA 00085 *> \verbatim 00086 *> LDSA is INTEGER 00087 *> The leading dimension of the array SA. LDSA >= max(1,M). 00088 *> \endverbatim 00089 *> 00090 *> \param[out] INFO 00091 *> \verbatim 00092 *> INFO is INTEGER 00093 *> = 0: successful exit. 00094 *> = 1: an entry of the matrix A is greater than the SINGLE 00095 *> PRECISION overflow threshold, in this case, the content 00096 *> of the UPLO part of SA in exit is unspecified. 00097 *> \endverbatim 00098 * 00099 * Authors: 00100 * ======== 00101 * 00102 *> \author Univ. of Tennessee 00103 *> \author Univ. of California Berkeley 00104 *> \author Univ. of Colorado Denver 00105 *> \author NAG Ltd. 00106 * 00107 *> \date November 2011 00108 * 00109 *> \ingroup complex16OTHERauxiliary 00110 * 00111 * ===================================================================== 00112 SUBROUTINE ZLAT2C( UPLO, N, A, LDA, SA, LDSA, INFO ) 00113 * 00114 * -- LAPACK auxiliary routine (version 3.4.0) -- 00115 * -- LAPACK is a software package provided by Univ. of Tennessee, -- 00116 * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- 00117 * November 2011 00118 * 00119 * .. Scalar Arguments .. 00120 CHARACTER UPLO 00121 INTEGER INFO, LDA, LDSA, N 00122 * .. 00123 * .. Array Arguments .. 00124 COMPLEX SA( LDSA, * ) 00125 COMPLEX*16 A( LDA, * ) 00126 * .. 00127 * 00128 * ===================================================================== 00129 * 00130 * .. Local Scalars .. 00131 INTEGER I, J 00132 DOUBLE PRECISION RMAX 00133 LOGICAL UPPER 00134 * .. 00135 * .. Intrinsic Functions .. 00136 INTRINSIC DBLE, DIMAG 00137 * .. 00138 * .. External Functions .. 00139 REAL SLAMCH 00140 LOGICAL LSAME 00141 EXTERNAL SLAMCH, LSAME 00142 * .. 00143 * .. Executable Statements .. 00144 * 00145 RMAX = SLAMCH( 'O' ) 00146 UPPER = LSAME( UPLO, 'U' ) 00147 IF( UPPER ) THEN 00148 DO 20 J = 1, N 00149 DO 10 I = 1, J 00150 IF( ( DBLE( A( I, J ) ).LT.-RMAX ) .OR. 00151 $ ( DBLE( A( I, J ) ).GT.RMAX ) .OR. 00152 $ ( DIMAG( A( I, J ) ).LT.-RMAX ) .OR. 00153 $ ( DIMAG( A( I, J ) ).GT.RMAX ) ) THEN 00154 INFO = 1 00155 GO TO 50 00156 END IF 00157 SA( I, J ) = A( I, J ) 00158 10 CONTINUE 00159 20 CONTINUE 00160 ELSE 00161 DO 40 J = 1, N 00162 DO 30 I = J, N 00163 IF( ( DBLE( A( I, J ) ).LT.-RMAX ) .OR. 00164 $ ( DBLE( A( I, J ) ).GT.RMAX ) .OR. 00165 $ ( DIMAG( A( I, J ) ).LT.-RMAX ) .OR. 00166 $ ( DIMAG( A( I, J ) ).GT.RMAX ) ) THEN 00167 INFO = 1 00168 GO TO 50 00169 END IF 00170 SA( I, J ) = A( I, J ) 00171 30 CONTINUE 00172 40 CONTINUE 00173 END IF 00174 50 CONTINUE 00175 * 00176 RETURN 00177 * 00178 * End of ZLAT2C 00179 * 00180 END