tahoma2d/thirdparty/openblas/xianyi-OpenBLAS-e6e87a2/reference/cdotuf.f
2016-03-24 02:47:04 +09:00

37 lines
894 B
Fortran

complex function cdotuf(n,cx,incx,cy,incy)
c
c forms the dot product of two vectors.
c jack dongarra, linpack, 3/11/78.
c modified 12/3/93, array(1) declarations changed to array(*)
c
complex cx(*),cy(*),ctemp
integer i,incx,incy,ix,iy,n
c
ctemp = (0.0,0.0)
cdotuf = (0.0,0.0)
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
ctemp = ctemp + cx(ix)*cy(iy)
ix = ix + incx
iy = iy + incy
10 continue
cdotuf = ctemp
return
c
c code for both increments equal to 1
c
20 do 30 i = 1,n
ctemp = ctemp + cx(i)*cy(i)
30 continue
cdotuf = ctemp
return
end