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Diffstat (limited to 'src/fortran/blas/zdotc.f')
-rw-r--r-- | src/fortran/blas/zdotc.f | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/src/fortran/blas/zdotc.f b/src/fortran/blas/zdotc.f new file mode 100644 index 0000000..d6ac685 --- /dev/null +++ b/src/fortran/blas/zdotc.f @@ -0,0 +1,36 @@ + double complex function zdotc(n,zx,incx,zy,incy) +c +c forms the dot product of a vector. +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 + ztemp = (0.0d0,0.0d0) + zdotc = (0.0d0,0.0d0) + 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 + ztemp = ztemp + dconjg(zx(ix))*zy(iy) + ix = ix + incx + iy = iy + incy + 10 continue + zdotc = ztemp + return +c +c code for both increments equal to 1 +c + 20 do 30 i = 1,n + ztemp = ztemp + dconjg(zx(i))*zy(i) + 30 continue + zdotc = ztemp + return + end |