Book a Demo!
CoCalc Logo Icon
StoreFeaturesDocsShareSupportNewsAboutPoliciesSign UpSign In
ElmerCSC
GitHub Repository: ElmerCSC/elmerfem
Path: blob/devel/mathlibs/src/blas/caxpy.f
5192 views
1
subroutine caxpy(n,ca,cx,incx,cy,incy)
2
c
3
c constant times a vector plus a vector.
4
c jack dongarra, linpack, 3/11/78.
5
c modified 12/3/93, array(1) declarations changed to array(*)
6
c
7
complex cx(*),cy(*),ca
8
integer i,incx,incy,ix,iy,n
9
c
10
if(n.le.0)return
11
if (abs(real(ca)) + abs(aimag(ca)) .eq. 0.0 ) 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
cy(iy) = cy(iy) + ca*cx(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
20 do 30 i = 1,n
31
cy(i) = cy(i) + ca*cx(i)
32
30 continue
33
return
34
end
35
36