.TH ZSCAL 3 "16 October 1992" "BLAS routine" "BLAS routine"
.SH NAME
ZSCAL - scales a vector by a constant.
.SH SYNOPSIS
.TP 31
subroutine zscal(n,za,zx,incx)
.TP 31
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c
scales a vector by a constant.
.TP 31
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c
jack dongarra, 3/11/78.
.TP 31
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c
modified to correct problem with negative increment, 8/21/90.
.TP 31
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double
complex za,zx(1)
.TP 31
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integer
i,incx,ix,n
.TP 31
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if(n.le.0)return
.TP 31
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if(incx.eq.1)go
to 20
.TP 31
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c
code for increment not equal to 1
.TP 31
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ix
= 1
.TP 31
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if(incx.lt.0)ix
= (-n+1)*incx + 1
.TP 31
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do
10 i = 1,n
.TP 31
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zx(ix)
= za*zx(ix)
.TP 31
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ix
= ix + incx
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10
continue
.TP 31
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return
.TP 31
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c
code for increment equal to 1
.TP 31
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20
do 30 i = 1,n
.TP 31
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zx(i)
= za*zx(i)
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30
continue
.TP 31
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return
.TP 31
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end
.SH PURPOSE