Displaying 1 result from an estimated 1 matches for "cos_ij".
2007 Jul 23
1
code optimization tips
...s)),
> nrow = 2, byrow = TRUE)
> }
> rj<-positions(N)*spacing # all positions in the 2N x 2N array
> rj<-rj[1:2,-((dim(rj)[2]-1)/2+1)] # remove rj=(0,0)
>
> mod<-function(x){sqrt(x[1]^2+x[2]^2)} # modulus
>
> sij <-function(rj){
> rij=mod(rj-ri)
> cos_ij=rj[1]/rij
> sin_ij=rj[2]/rij
>
> A<-(1-1i*k*rij)*(3*cos_ij^2-1)*exp(1i*k*rij)/(rij^3)
> B<-k^2*sin_ij^2*exp(1i*k*rij)/rij
>
> sij<-A+B
> }
>
> s_ij<-apply(rj,2,sij)
> S<-sum(s_ij)
> alpha_s/(1-alpha_s*S)
> }
> alpha_c()
This function is to be...