KTH framework for Nek5000 toolboxes; testing version  0.0.1
zswap.f
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1  subroutine zswap (n,zx,incx,zy,incy)
2 c
3 c interchanges two vectors.
4 c jack dongarra, 3/11/78.
5 c modified 12/3/93, array(1) declarations changed to array(*)
6 c
7  double complex zx(*),zy(*),ztemp
8  integer i,incx,incy,ix,iy,n
9 c
10  if(n.le.0)return
11  if(incx.eq.1.and.incy.eq.1)go to 20
12 c
13 c code for unequal increments or equal increments not equal
14 c to 1
15 c
16  ix = 1
17  iy = 1
18  if(incx.lt.0)ix = (-n+1)*incx + 1
19  if(incy.lt.0)iy = (-n+1)*incy + 1
20  do 10 i = 1,n
21  ztemp = zx(ix)
22  zx(ix) = zy(iy)
23  zy(iy) = ztemp
24  ix = ix + incx
25  iy = iy + incy
26  10 continue
27  return
28 c
29 c code for both increments equal to 1
30  20 do 30 i = 1,n
31  ztemp = zx(i)
32  zx(i) = zy(i)
33  zy(i) = ztemp
34  30 continue
35  return
36  end
zswap
subroutine zswap(n, zx, incx, zy, incy)
Definition: zswap.f:2