CAXPY constant times a vector plus a vector.
Type | Intent | Optional | Attributes | Name | ||
---|---|---|---|---|---|---|
integer(kind=ilp), | intent(in) | :: | n | |||
complex(kind=sp), | intent(in) | :: | ca | |||
complex(kind=sp), | intent(in) | :: | cx(*) | |||
integer(kind=ilp), | intent(in) | :: | incx | |||
complex(kind=sp), | intent(inout) | :: | cy(*) | |||
integer(kind=ilp), | intent(in) | :: | incy |
pure subroutine stdlib_caxpy(n,ca,cx,incx,cy,incy) !! CAXPY constant times a vector plus a vector. ! -- reference blas level1 routine -- ! -- reference blas is a software package provided by univ. of tennessee, -- ! -- univ. of california berkeley, univ. of colorado denver and nag ltd..-- ! Scalar Arguments complex(sp), intent(in) :: ca integer(ilp), intent(in) :: incx, incy, n ! Array Arguments complex(sp), intent(in) :: cx(*) complex(sp), intent(inout) :: cy(*) ! ===================================================================== ! Local Scalars integer(ilp) :: i, ix, iy if (n<=0) return if (stdlib_cabs1(ca)==0.0e+0_sp) return if (incx==1 .and. incy==1) then ! code for both increments equal to 1 do i = 1,n cy(i) = cy(i) + ca*cx(i) end do else ! code for unequal increments or equal increments ! not equal to 1 ix = 1 iy = 1 if (incx<0) ix = (-n+1)*incx + 1 if (incy<0) iy = (-n+1)*incy + 1 do i = 1,n cy(iy) = cy(iy) + ca*cx(ix) ix = ix + incx iy = iy + incy end do end if return end subroutine stdlib_caxpy