| 1 |
aw0a |
1 |
C dcopy.f |
| 2 |
|
|
C is freely available from netlib. It is not subject to any GNU License |
| 3 |
|
|
C set by the authors of the ASCEND math programming system. |
| 4 |
|
|
C $Date: 1996/04/30 18:14:07 $ $Revision: 1.1.1.1 $ |
| 5 |
|
|
C |
| 6 |
|
|
subroutine dcopy(n,dx,incx,dy,incy) |
| 7 |
|
|
c |
| 8 |
|
|
c copies a vector, x, to a vector, y. |
| 9 |
|
|
c uses unrolled loops for increments equal to one. |
| 10 |
|
|
c jack dongarra, linpack, 3/11/78. |
| 11 |
|
|
c |
| 12 |
|
|
double precision dx(*),dy(*) |
| 13 |
|
|
integer i,incx,incy,ix,iy,m,mp1,n |
| 14 |
|
|
c |
| 15 |
|
|
if(n.le.0)return |
| 16 |
|
|
if(incx.eq.1.and.incy.eq.1)go to 20 |
| 17 |
|
|
c |
| 18 |
|
|
c code for unequal increments or equal increments |
| 19 |
|
|
c not equal to 1 |
| 20 |
|
|
c |
| 21 |
|
|
ix = 1 |
| 22 |
|
|
iy = 1 |
| 23 |
|
|
if(incx.lt.0)ix = (-n+1)*incx + 1 |
| 24 |
|
|
if(incy.lt.0)iy = (-n+1)*incy + 1 |
| 25 |
|
|
do 10 i = 1,n |
| 26 |
|
|
dy(iy) = dx(ix) |
| 27 |
|
|
ix = ix + incx |
| 28 |
|
|
iy = iy + incy |
| 29 |
|
|
10 continue |
| 30 |
|
|
return |
| 31 |
|
|
c |
| 32 |
|
|
c code for both increments equal to 1 |
| 33 |
|
|
c |
| 34 |
|
|
c |
| 35 |
|
|
c clean-up loop |
| 36 |
|
|
c |
| 37 |
|
|
20 m = mod(n,7) |
| 38 |
|
|
if( m .eq. 0 ) go to 40 |
| 39 |
|
|
do 30 i = 1,m |
| 40 |
|
|
dy(i) = dx(i) |
| 41 |
|
|
30 continue |
| 42 |
|
|
if( n .lt. 7 ) return |
| 43 |
|
|
40 mp1 = m + 1 |
| 44 |
|
|
do 50 i = mp1,n,7 |
| 45 |
|
|
dy(i) = dx(i) |
| 46 |
|
|
dy(i + 1) = dx(i + 1) |
| 47 |
|
|
dy(i + 2) = dx(i + 2) |
| 48 |
|
|
dy(i + 3) = dx(i + 3) |
| 49 |
|
|
dy(i + 4) = dx(i + 4) |
| 50 |
|
|
dy(i + 5) = dx(i + 5) |
| 51 |
|
|
dy(i + 6) = dx(i + 6) |
| 52 |
|
|
50 continue |
| 53 |
|
|
return |
| 54 |
|
|
end |
| 55 |
|
|
|
Parent Directory
| 
Revision Log