LAPACK 3.12.0
LAPACK: Linear Algebra PACKage
Loading...
Searching...
No Matches

◆ cscal()

subroutine cscal ( integer  n,
complex  ca,
complex, dimension(*)  cx,
integer  incx 
)

CSCAL

Purpose:
    CSCAL scales a vector by a constant.
Parameters
[in]N
          N is INTEGER
         number of elements in input vector(s)
[in]CA
          CA is COMPLEX
           On entry, CA specifies the scalar alpha.
[in,out]CX
          CX is COMPLEX array, dimension ( 1 + ( N - 1 )*abs( INCX ) )
[in]INCX
          INCX is INTEGER
         storage spacing between elements of CX
Author
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Further Details:
     jack dongarra, linpack,  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 cscal.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 CA
85 INTEGER INCX,N
86* ..
87* .. Array Arguments ..
88 COMPLEX CX(*)
89* ..
90*
91* =====================================================================
92*
93* .. Local Scalars ..
94 INTEGER I,NINCX
95* ..
96* .. Parameters ..
97 COMPLEX ONE
98 parameter(one= (1.0e+0,0.0e+0))
99* ..
100 IF (n.LE.0 .OR. incx.LE.0 .OR. ca.EQ.one) RETURN
101 IF (incx.EQ.1) THEN
102*
103* code for increment equal to 1
104*
105 DO i = 1,n
106 cx(i) = ca*cx(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 cx(i) = ca*cx(i)
115 END DO
116 END IF
117 RETURN
118*
119* End of CSCAL
120*