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double complex function zdotc(n,zx,incx,zy,incy)
c
c forms the dot product of a vector.
c jack dongarra, 3/11/78.
c modified 12/3/93, array(1) declarations changed to array(*)
c
double complex zx(*),zy(*),ztemp
integer i,incx,incy,ix,iy,n
ztemp = (0.0d0,0.0d0)
zdotc = (0.0d0,0.0d0)
if(n.le.0)return
if(incx.eq.1.and.incy.eq.1)go to 20
c
c code for unequal increments or equal increments
c not equal to 1
c
ix = 1
iy = 1
if(incx.lt.0)ix = (-n+1)*incx + 1
if(incy.lt.0)iy = (-n+1)*incy + 1
do 10 i = 1,n
ztemp = ztemp + dconjg(zx(ix))*zy(iy)
ix = ix + incx
iy = iy + incy
10 continue
zdotc = ztemp
return
c
c code for both increments equal to 1
c
20 do 30 i = 1,n
ztemp = ztemp + dconjg(zx(i))*zy(i)
30 continue
zdotc = ztemp
return
end
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