how to calculate Somme of vector elements ?

i would like to calculate the somme k=1:10^5 of 1/k^2,using the command sum, can anyone help me ?

Answer 1

[madhan ravi]

k=1:10.^5;
sum(1./(k.^2))

[diadalina]

thanks mr madhanravi for response, but this way doesn't work in matlab 2009b is there any other way to do this, thanks in advance.

[madhan ravi]

try the edited code

[diadalina]

thnks, that's what i want.

[madhan ravi]

Anytime :)

[diadalina]

is there any method to verify the obtained result ?

[Bruno Luong]

"is there any method to verify the obtained result ?"

    s = sum(1./(k.^2))
    s / (pi^2/6)

That gives

s =

      1.6449

ans =

      1.0000

Seems alright to me.

Answer 2

[mohamed]

I need instructions that I write in MATLAB, to give me the result of this sum

[DGM]

Without knowing what x or t are:

x = something
t = something
n = 0:1000;

t1 = 1/(pi^2*(2*n + 1)^2);
t2 = pi*(2*n + 1)*(x - 1)/2;
U = 800*sum(t1*cos(t2)*exp(-0.3738)*(2*n + 1)^2*t)

[mohamed]

Thanks dude, just forgot to mention that "x" changes from 0 to 2, and t is the time