KTH framework for Nek5000 toolboxes; testing version  0.0.1
dcopy.f
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1  subroutine dcopy(n,dx,incx,dy,incy)
2 c
3 c copies a vector, x, to a vector, y.
4 c uses unrolled loops for increments equal to one.
5 c jack dongarra, linpack, 3/11/78.
6 c modified 12/3/93, array(1) declarations changed to array(*)
7 c
8  double precision dx(*),dy(*)
9  integer i,incx,incy,ix,iy,m,mp1,n
10 c
11  if(n.le.0)return
12  if(incx.eq.1.and.incy.eq.1)go to 20
13 c
14 c code for unequal increments or equal increments
15 c not equal to 1
16 c
17  ix = 1
18  iy = 1
19  if(incx.lt.0)ix = (-n+1)*incx + 1
20  if(incy.lt.0)iy = (-n+1)*incy + 1
21  do 10 i = 1,n
22  dy(iy) = dx(ix)
23  ix = ix + incx
24  iy = iy + incy
25  10 continue
26  return
27 c
28 c code for both increments equal to 1
29 c
30 c
31 c clean-up loop
32 c
33  20 m = mod(n,7)
34  if( m .eq. 0 ) go to 40
35  do 30 i = 1,m
36  dy(i) = dx(i)
37  30 continue
38  if( n .lt. 7 ) return
39  40 mp1 = m + 1
40  do 50 i = mp1,n,7
41  dy(i) = dx(i)
42  dy(i + 1) = dx(i + 1)
43  dy(i + 2) = dx(i + 2)
44  dy(i + 3) = dx(i + 3)
45  dy(i + 4) = dx(i + 4)
46  dy(i + 5) = dx(i + 5)
47  dy(i + 6) = dx(i + 6)
48  50 continue
49  return
50  end
dcopy
subroutine dcopy(n, dx, incx, dy, incy)
Definition: dcopy.f:2