LAPACK 3.12.0 LAPACK: Linear Algebra PACKage
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## ◆ zscal()

 subroutine zscal ( integer n, complex*16 za, complex*16, dimension(*) zx, integer incx )

ZSCAL

Purpose:
`    ZSCAL scales a vector by a constant.`
Parameters
 [in] N ``` N is INTEGER number of elements in input vector(s)``` [in] ZA ``` ZA is COMPLEX*16 On entry, ZA specifies the scalar alpha.``` [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 77 of file zscal.f.

78*
79* -- Reference BLAS level1 routine --
80* -- Reference BLAS is a software package provided by Univ. of Tennessee, --
81* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
82*
83* .. Scalar Arguments ..
84 COMPLEX*16 ZA
85 INTEGER INCX,N
86* ..
87* .. Array Arguments ..
88 COMPLEX*16 ZX(*)
89* ..
90*
91* =====================================================================
92*
93* .. Local Scalars ..
94 INTEGER I,NINCX
95* ..
96* .. Parameters ..
97 COMPLEX*16 ONE
98 parameter(one= (1.0d+0,0.0d+0))
99* ..
100 IF (n.LE.0 .OR. incx.LE.0 .OR. za.EQ.one) RETURN
101 IF (incx.EQ.1) THEN
102*
103* code for increment equal to 1
104*
105 DO i = 1,n
106 zx(i) = za*zx(i)
107 END DO
108 ELSE
109*
110* code for increment not equal to 1
111*
112 nincx = n*incx
113 DO i = 1,nincx,incx
114 zx(i) = za*zx(i)
115 END DO
116 END IF
117 RETURN
118*
119* End of ZSCAL
120*