help me with for loop

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

[Stephen23]

"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?

Answer 1

[William Rose]

@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.