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LAPACK
3.4.1
LAPACK: Linear Algebra PACKage
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00001 *> \brief \b CDOTU 00002 * 00003 * =========== DOCUMENTATION =========== 00004 * 00005 * Online html documentation available at 00006 * http://www.netlib.org/lapack/explore-html/ 00007 * 00008 * Definition: 00009 * =========== 00010 * 00011 * COMPLEX FUNCTION CDOTU(N,CX,INCX,CY,INCY) 00012 * 00013 * .. Scalar Arguments .. 00014 * INTEGER INCX,INCY,N 00015 * .. 00016 * .. Array Arguments .. 00017 * COMPLEX CX(*),CY(*) 00018 * .. 00019 * 00020 * 00021 *> \par Purpose: 00022 * ============= 00023 *> 00024 *> \verbatim 00025 *> 00026 *> CDOTU forms the dot product of two vectors. 00027 *> \endverbatim 00028 * 00029 * Authors: 00030 * ======== 00031 * 00032 *> \author Univ. of Tennessee 00033 *> \author Univ. of California Berkeley 00034 *> \author Univ. of Colorado Denver 00035 *> \author NAG Ltd. 00036 * 00037 *> \date November 2011 00038 * 00039 *> \ingroup complex_blas_level1 00040 * 00041 *> \par Further Details: 00042 * ===================== 00043 *> 00044 *> \verbatim 00045 *> 00046 *> jack dongarra, linpack, 3/11/78. 00047 *> modified 12/3/93, array(1) declarations changed to array(*) 00048 *> \endverbatim 00049 *> 00050 * ===================================================================== 00051 COMPLEX FUNCTION CDOTU(N,CX,INCX,CY,INCY) 00052 * 00053 * -- Reference BLAS level1 routine (version 3.4.0) -- 00054 * -- Reference BLAS is a software package provided by Univ. of Tennessee, -- 00055 * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- 00056 * November 2011 00057 * 00058 * .. Scalar Arguments .. 00059 INTEGER INCX,INCY,N 00060 * .. 00061 * .. Array Arguments .. 00062 COMPLEX CX(*),CY(*) 00063 * .. 00064 * 00065 * ===================================================================== 00066 * 00067 * .. Local Scalars .. 00068 COMPLEX CTEMP 00069 INTEGER I,IX,IY 00070 * .. 00071 CTEMP = (0.0,0.0) 00072 CDOTU = (0.0,0.0) 00073 IF (N.LE.0) RETURN 00074 IF (INCX.EQ.1 .AND. INCY.EQ.1) THEN 00075 * 00076 * code for both increments equal to 1 00077 * 00078 DO I = 1,N 00079 CTEMP = CTEMP + CX(I)*CY(I) 00080 END DO 00081 ELSE 00082 * 00083 * code for unequal increments or equal increments 00084 * not equal to 1 00085 * 00086 IX = 1 00087 IY = 1 00088 IF (INCX.LT.0) IX = (-N+1)*INCX + 1 00089 IF (INCY.LT.0) IY = (-N+1)*INCY + 1 00090 DO I = 1,N 00091 CTEMP = CTEMP + CX(IX)*CY(IY) 00092 IX = IX + INCX 00093 IY = IY + INCY 00094 END DO 00095 END IF 00096 CDOTU = CTEMP 00097 RETURN 00098 END