what is the error Matrix dimensions must agree.?

code:

clc
clear all;

x=linspace(-10,10,1000);
t=0:1:20;
k=10;
l=10;

u_x=2*k*x/l.*(x>0 & x<l/2)+2*k*(1-x)/l.*(x>l/2 & x<l/2);
plot(x,u_x)

s=0;

for n=1:1:1000
   s=s+(1/n.^2).*sin(n.*pi/2).*cos(n.*pi.*t/l).*sin(n.*pi.*x/l); 
end

u_x_t=(8*k/pi^2)*s;

................................................

error:

Matrix dimensions must agree.

Error in Untitled (line 16)

s=s+(1/n.^2).*sin(n.*pi/2).*cos(n.*pi.*t/l).*sin(n.*pi.*x/l);

[Walter Roberson]

Please do not close questions that have an answer.

Answer 1

[Walter Roberson]

t is length 21. cos n pi t over l will be length 21

x is length 1000. sin n pi x over l will be length 1000

you are trying to .* those two together . What is your expectations about the size of the results ?