Summation with FOR Loop

Hello, Super noob question, but how do I do the attached picture in MatLab using a FOR loop. I just need to know how to set up the loop, not the actual values. Thanks for any help!

Answer 1

[Torsten]

omega=...;
t=...;

N=...;
summe = 0.0;
for k=1:N
  summe = summe + sin(omega*t*(2*k-1))/(2*k-1);
end

Best wishes

Torsten.

[Me29]

I don't think that is correct.. Given t=0:20, N=1000, omega=1, it should look like a square wave. The function basically sums a series of sine functions and approximates a square wave. Using your code, it doesn't do that... Any other ideas? Thanks!

[Torsten]

Try

t=0:2/pi/100:2/pi
omega=1;

N=1000;
summe = 0.0;
for k=1:N
  summe = summe + sin(omega*t*(2*k-1))/(2*k-1);
end

plot(t,4/pi*summe)

Best wishes

Torsten.

Answer 2

[Jan]

You cannot run a loop from 1 to infinity in Matlab. Either solve the summation symbolically or find out, if this sum converges and you can use a certain number of elements to get the result with a wanted accuracy.

[Me29]

Sorry failed to mention, assume the limit of the summation is a real value input from the user. I just need the setup for the FOR loop.

Answer 3

[Arzu Ahmadova]

Hi,

Could you explain please how to code more than 2 different inifinite sums in loop?

[Cameron Cooke]

no

Answer 4

[daniel domshlak]

i=0;

x = input ('choose the initial value : ');

y = input ('choose final value : ');

n=(x:y);

summe=0;

for i=x:y

a=(i*2+1).^3;

summe = summe + a;

end

summe

[daniel domshlak]

not relevant to the qustion but I had an exersise to write a summation code not using sum function, and not found answears so i upload this.

[daniel domshlak]

if someone finds a way to shorten this, don't hassitate to sahare.

[Arzu Ahmadova]

Thanks