help me with for loop

2 次查看（过去 30 天）
nirwana
nirwana 2023-9-15
回答： William Rose 2023-9-23
I know this is very basic question, but i still has difficulty to answer it
i try to add some fourier series to prove gibbs effect
here my coding
t=0:0.01:7;
%odd series
yo= sin(t) + sin(3*t)/3 + sin(5*t)/5 + sin(7*t)/7 + sin(9*t)/9+sin(11*t)/11;
yoo=sin(13*t)/13+sin(15*t)/15+sin(17*t)/17+sin(19*t)/19+sin(21*t)/21;
subplot(211), plot(t,(yo+yoo)),title('fourier odd series')
%even series
ye= sin(0*t) + sin(2*t)/2 + sin(4*t)/4 + sin(6*t)/6 + sin(8*t)/8+sin(10*t)/10;
subplot(212), plot(t,ye), title('fourier even series')
instead of putting long equation, i would like to put it in for loop. can you help me to "rearange" my code neatly in foor loop.
my other question is : which one better to do it, for loop or vectorization (my teacher said that foor loop) must be avoid because it slower computational time
  1 个评论
Stephen23
Stephen23 2023-9-15
编辑：Stephen23 2023-9-15
"which one better to do it, for loop or vectorization (my teacher said that foor loop) must be avoid because it slower computational time"
For such a simple calculation I doubt there would be much difference. Overall (code runtime + write time + debug time + maintenance time) vectorized code is more efficient: you already have it and presumably it does what you want.
But go ahead: test them both and let us know.
"instead of putting long equation, i would like to put it in for loop. can you help me to "rearange" my code neatly in foor loop."
There are two posisble things you could loop over: 1) the elements of t or 2) the terms of the fourier series: which one do you want to loop over?

请先登录，再进行评论。

请先登录，再回答此问题。

采纳的回答

William Rose
William Rose 2023-9-23
Ran in:
@nirwana,
@Stephen23 knows more about Matlab than almost anybody. When he says "I doubt there is much of a difference", I think he knows the answer and he is encouraging you to find out for yourself.
Your other question was how to replace a line such as
t=(0:.01:2)*2*pi;
yo= sin(t) + sin(3*t)/3 + sin(5*t)/5 + sin(7*t)/7 + sin(9*t)/9+sin(11*t)/11;
with a for loop.
yoloop=0;
for i=1:2:11
yoloop=yoloop+sin(i*t)/i;
end
Plot result
plot(t,yo,'-rx',t,yoloop,'-go');
legend('yo','yoloop')
You can see the GIbbs effect. Try this idea for yoo and ye.

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Loops and Conditional Statements 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by