how to simplify/solve a trigonometric function

I have this function, it is a solar radiation per second (ii) over a year (jj) and it is taking the most time to be solved:

Gincl(ii,jj)=G(ii,jj).*cosd(angle)+1000*(-sind(a(jj)).*cosd(lat)*sind(angle).*cosd(0)+cosd(a(jj)).*sind(lat).*cosd(0).*sind(angle).*cosd(H(ii))+cosd(a(jj)).*sind(0).*sind(angle).*sind(H(ii)));

is there any way to solve this equation in matlab, so it takes less time? I am not using any build in block (don't know how) and it is written as it is in the .m file. thanks.