diff options
Diffstat (limited to '2.3-1/src/fortran/blas/zswap.f')
-rw-r--r-- | 2.3-1/src/fortran/blas/zswap.f | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/2.3-1/src/fortran/blas/zswap.f b/2.3-1/src/fortran/blas/zswap.f new file mode 100644 index 00000000..f28a4e41 --- /dev/null +++ b/2.3-1/src/fortran/blas/zswap.f @@ -0,0 +1,36 @@ + subroutine zswap (n,zx,incx,zy,incy) +c +c interchanges two vectors. +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 +c + 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 not equal +c 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 = zx(ix) + zx(ix) = zy(iy) + zy(iy) = ztemp + ix = ix + incx + iy = iy + incy + 10 continue + return +c +c code for both increments equal to 1 + 20 do 30 i = 1,n + ztemp = zx(i) + zx(i) = zy(i) + zy(i) = ztemp + 30 continue + return + end |