LAPACK 3.11.0 LAPACK: Linear Algebra PACKage
Loading...
Searching...
No Matches

## ◆ 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 double 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```
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 71 of file dzasum.f.

72*
73* -- Reference BLAS level1 routine --
74* -- Reference BLAS is a software package provided by Univ. of Tennessee, --
75* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
76*
77* .. Scalar Arguments ..
78 INTEGER INCX,N
79* ..
80* .. Array Arguments ..
81 COMPLEX*16 ZX(*)
82* ..
83*
84* =====================================================================
85*
86* .. Local Scalars ..
87 DOUBLE PRECISION STEMP
88 INTEGER I,NINCX
89* ..
90* .. External Functions ..
91 DOUBLE PRECISION DCABS1
92 EXTERNAL dcabs1
93* ..
94 dzasum = 0.0d0
95 stemp = 0.0d0
96 IF (n.LE.0 .OR. incx.LE.0) RETURN
97 IF (incx.EQ.1) THEN
98*
99* code for increment equal to 1
100*
101 DO i = 1,n
102 stemp = stemp + dcabs1(zx(i))
103 END DO
104 ELSE
105*
106* code for increment not equal to 1
107*
108 nincx = n*incx
109 DO i = 1,nincx,incx
110 stemp = stemp + dcabs1(zx(i))
111 END DO
112 END IF
113 dzasum = stemp
114 RETURN
115*
116* End of DZASUM
117*
double precision function dcabs1(Z)
DCABS1
Definition: dcabs1.f:47
double precision function dzasum(N, ZX, INCX)
DZASUM
Definition: dzasum.f:72
Here is the call graph for this function:
Here is the caller graph for this function: