make the for loop run faster

I would appreciate any help to optimize this code since it runs 86400x365x19x37 times:

for ii = 1 : length(time)

if time(ii)<=sunrise

Ta(ii)=Tmin;

elseif time(ii)>=sunrise && time(ii)<=Tmax_time

Ta(ii)=Tmin+(Tmax-Tmin)*sin((time(ii)-sunrise)/(Tmax_time-sunrise)*pi/2);

elseif time(ii)>Tmax_time && time(ii)<=sunset

Ta(ii)=T0+(Tmax-T0)*sin(pi/2+(time(ii)-Tmax_time)*pi/(2*4));

elseif time(ii)>sunset && time(ii)<=Day_end

Ta(ii)=T0+(Tmin-T0)/(Day_end-sunset).^0.75*(time(ii)-sunset).^0.75;

end

end

thanks

Answer 1

[infinity]

Hello,

How about if you try to use this

time = 1:100;
T0 = 0;
sunrise = 10;
Tmin = 1;
Tmax = 100;
Tmax_time = 50;
sunset = 70;
Day_end = 100;

Ta = (time <= sunrise).* Tmin...
    + (time > sunrise & time <=Tmax_time).*...
    (Tmin+(Tmax-Tmin)*sin((time-sunrise)/(Tmax_time-sunrise)*pi/2)) ... 
    + (time > Tmax_time & time <=sunset).*...
    (T0+(Tmax-T0)*sin(pi/2+(time-Tmax_time)*pi/(2*4)))...
    + (time>sunset & time<=Day_end).*...
(T0+(Tmin-T0)/(Day_end-sunset).^0.75*(time-sunset).^0.75);

You could apply for your data of "time, T0, sunrise, etc.".

[Asliddin Komilov]

Elapsed time is 2 times shorter.

thanks