How to tabulate?
显示 更早的评论
hello friends i want to ask a question regarding tabulation of number of days and sdelta without the statistic toolbox.
dn=1:1:365;
x=(360/365*(dn+284));
sdelta=23.45*(sind(x)*pi/180);
Tabulate sdelta for dn = 15, 45, 75, 105, 135, 165, 195, 225, 255, 285, 315, 345.
for normal tabulation for dn and sdelta is easy i believe but how about when the number of days is like this?i did thought about interpolation but i think it would not be that complicated and must have a simpler way to solve it ..can anyone give me a hint or guide me?.Thank you friends
采纳的回答
KSSV
2022-1-29
You can use interp1.
dn=1:1:365;
x=(360/365*(dn+284));
sdelta=23.45*(sind(x)*pi/180);
dni = [15, 45, 75, 105, 135, 165, 195, 225, 255, 285, 315, 345] ;
sdeltai = interp1(dn,x,dni);
更多回答（1 个）
You do not need to interpolate because the dn values you want the sdelta for are all already in the vector of all dn values (i.e., 1:1:365 contains 15, 45, 75, ...); you merely need to take those indices of sdelta:
dn=1:1:365;
x=(360/365*(dn+284));
sdelta=23.45*(sind(x)*pi/180);
dni = [15, 45, 75, 105, 135, 165, 195, 225, 255, 285, 315, 345];
sdeltai = sdelta(dni) % get elements of sdelta at indices dni
isequal(sdeltai,interp1(dn,sdelta,dni)) % same as "interpolating"
类别
在 帮助中心 和 File Exchange 中查找有关 Matrix Indexing 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
