LAPACK  3.9.0
LAPACK: Linear Algebra PACKage

◆ dzasum()

double precision function dzasum ( integer  N,
complex*16, dimension(*)  ZX,
integer  INCX 
)

DZASUM

Purpose:
    DZASUM takes the sum of the (|Re(.)| + |Im(.)|)'s of a complex vector and
    returns a single precision result.
Parameters
[in]N
          N is INTEGER
         number of elements in input vector(s)
[in,out]ZX
          ZX is COMPLEX*16 array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
[in]INCX
          INCX is INTEGER
         storage spacing between elements of ZX
Author
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Date
November 2017
Further Details:
     jack dongarra, 3/11/78.
     modified 3/93 to return if incx .le. 0.
     modified 12/3/93, array(1) declarations changed to array(*)

Definition at line 74 of file dzasum.f.

74 *
75 * -- Reference BLAS level1 routine (version 3.8.0) --
76 * -- Reference BLAS is a software package provided by Univ. of Tennessee, --
77 * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
78 * November 2017
79 *
80 * .. Scalar Arguments ..
81  INTEGER INCX,N
82 * ..
83 * .. Array Arguments ..
84  COMPLEX*16 ZX(*)
85 * ..
86 *
87 * =====================================================================
88 *
89 * .. Local Scalars ..
90  DOUBLE PRECISION STEMP
91  INTEGER I,NINCX
92 * ..
93 * .. External Functions ..
94  DOUBLE PRECISION DCABS1
95  EXTERNAL dcabs1
96 * ..
97  dzasum = 0.0d0
98  stemp = 0.0d0
99  IF (n.LE.0 .OR. incx.LE.0) RETURN
100  IF (incx.EQ.1) THEN
101 *
102 * code for increment equal to 1
103 *
104  DO i = 1,n
105  stemp = stemp + dcabs1(zx(i))
106  END DO
107  ELSE
108 *
109 * code for increment not equal to 1
110 *
111  nincx = n*incx
112  DO i = 1,nincx,incx
113  stemp = stemp + dcabs1(zx(i))
114  END DO
115  END IF
116  dzasum = stemp
117  RETURN
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dzasum
double precision function dzasum(N, ZX, INCX)
DZASUM
Definition: dzasum.f:74
dcabs1
double precision function dcabs1(Z)
DCABS1
Definition: dcabs1.f:49