1*> \brief \b ZLAT2C converts a double complex triangular matrix to a complex triangular matrix.
2*
3*  =========== DOCUMENTATION ===========
4*
5* Online html documentation available at
6*            http://www.netlib.org/lapack/explore-html/
7*
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15*> [TXT]</a>
16*> \endhtmlonly
17*
18*  Definition:
19*  ===========
20*
21*       SUBROUTINE ZLAT2C( UPLO, N, A, LDA, SA, LDSA, INFO )
22*
23*       .. Scalar Arguments ..
24*       CHARACTER          UPLO
25*       INTEGER            INFO, LDA, LDSA, N
26*       ..
27*       .. Array Arguments ..
28*       COMPLEX            SA( LDSA, * )
29*       COMPLEX*16         A( LDA, * )
30*       ..
31*
32*
33*> \par Purpose:
34*  =============
35*>
36*> \verbatim
37*>
38*> ZLAT2C converts a COMPLEX*16 triangular matrix, SA, to a COMPLEX
39*> triangular matrix, A.
40*>
41*> RMAX is the overflow for the SINGLE PRECISION arithmetic
42*> ZLAT2C checks that all the entries of A are between -RMAX and
43*> RMAX. If not the convertion is aborted and a flag is raised.
44*>
45*> This is an auxiliary routine so there is no argument checking.
46*> \endverbatim
47*
48*  Arguments:
49*  ==========
50*
51*> \param[in] UPLO
52*> \verbatim
53*>          UPLO is CHARACTER*1
54*>          = 'U':  A is upper triangular;
55*>          = 'L':  A is lower triangular.
56*> \endverbatim
57*>
58*> \param[in] N
59*> \verbatim
60*>          N is INTEGER
61*>          The number of rows and columns of the matrix A.  N >= 0.
62*> \endverbatim
63*>
64*> \param[in] A
65*> \verbatim
66*>          A is COMPLEX*16 array, dimension (LDA,N)
67*>          On entry, the N-by-N triangular coefficient matrix A.
68*> \endverbatim
69*>
70*> \param[in] LDA
71*> \verbatim
72*>          LDA is INTEGER
73*>          The leading dimension of the array A.  LDA >= max(1,N).
74*> \endverbatim
75*>
76*> \param[out] SA
77*> \verbatim
78*>          SA is COMPLEX array, dimension (LDSA,N)
79*>          Only the UPLO part of SA is referenced.  On exit, if INFO=0,
80*>          the N-by-N coefficient matrix SA; if INFO>0, the content of
81*>          the UPLO part of SA is unspecified.
82*> \endverbatim
83*>
84*> \param[in] LDSA
85*> \verbatim
86*>          LDSA is INTEGER
87*>          The leading dimension of the array SA.  LDSA >= max(1,M).
88*> \endverbatim
89*>
90*> \param[out] INFO
91*> \verbatim
92*>          INFO is INTEGER
93*>          = 0:  successful exit.
94*>          = 1:  an entry of the matrix A is greater than the SINGLE
95*>                PRECISION overflow threshold, in this case, the content
96*>                of the UPLO part of SA in exit is unspecified.
97*> \endverbatim
98*
99*  Authors:
100*  ========
101*
102*> \author Univ. of Tennessee
103*> \author Univ. of California Berkeley
104*> \author Univ. of Colorado Denver
105*> \author NAG Ltd.
106*
107*> \date September 2012
108*
109*> \ingroup complex16OTHERauxiliary
110*
111*  =====================================================================
112      SUBROUTINE ZLAT2C( UPLO, N, A, LDA, SA, LDSA, INFO )
113*
114*  -- LAPACK auxiliary routine (version 3.4.2) --
115*  -- LAPACK is a software package provided by Univ. of Tennessee,    --
116*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
117*     September 2012
118*
119*     .. Scalar Arguments ..
120      CHARACTER          UPLO
121      INTEGER            INFO, LDA, LDSA, N
122*     ..
123*     .. Array Arguments ..
124      COMPLEX            SA( LDSA, * )
125      COMPLEX*16         A( LDA, * )
126*     ..
127*
128*  =====================================================================
129*
130*     .. Local Scalars ..
131      INTEGER            I, J
132      DOUBLE PRECISION   RMAX
133      LOGICAL            UPPER
134*     ..
135*     .. Intrinsic Functions ..
136      INTRINSIC          DBLE, DIMAG
137*     ..
138*     .. External Functions ..
139      REAL               SLAMCH
140      LOGICAL            LSAME
141      EXTERNAL           SLAMCH, LSAME
142*     ..
143*     .. Executable Statements ..
144*
145      RMAX = SLAMCH( 'O' )
146      UPPER = LSAME( UPLO, 'U' )
147      IF( UPPER ) THEN
148         DO 20 J = 1, N
149            DO 10 I = 1, J
150               IF( ( DBLE( A( I, J ) ).LT.-RMAX ) .OR.
151     $             ( DBLE( A( I, J ) ).GT.RMAX ) .OR.
152     $             ( DIMAG( A( I, J ) ).LT.-RMAX ) .OR.
153     $             ( DIMAG( A( I, J ) ).GT.RMAX ) ) THEN
154                  INFO = 1
155                  GO TO 50
156               END IF
157               SA( I, J ) = A( I, J )
158   10       CONTINUE
159   20    CONTINUE
160      ELSE
161         DO 40 J = 1, N
162            DO 30 I = J, N
163               IF( ( DBLE( A( I, J ) ).LT.-RMAX ) .OR.
164     $             ( DBLE( A( I, J ) ).GT.RMAX ) .OR.
165     $             ( DIMAG( A( I, J ) ).LT.-RMAX ) .OR.
166     $             ( DIMAG( A( I, J ) ).GT.RMAX ) ) THEN
167                  INFO = 1
168                  GO TO 50
169               END IF
170               SA( I, J ) = A( I, J )
171   30       CONTINUE
172   40    CONTINUE
173      END IF
174   50 CONTINUE
175*
176      RETURN
177*
178*     End of ZLAT2C
179*
180      END
181