How can I get this function to stop graphing a thousand straight lines and instead graph the data points it's supposed to?

When I call the following function, it should give me two nice bell curves. However, it's giving me a thousand straight lines on a single graph. How do I fix it so that I get the data points?

Here is the section of code:

function xprime = dcoupledeta(t,x)

c1 = 1;
c2 = 1;
E = .001;
m = 5;
k = 1;

s=size(t);
eta1 = zeros(1000,1);
eta2 = zeros(1000,1);
P = zeros(1,1000);
P2 = zeros(1,1000);

for j=1:s
    for i=1:s
    eta1(i) = .0001*i;
    eta2(i) = .001*i;

xprime(1)= x(3);
xprime(2)= x(4);
xprime(3)= -eta1(i)*(((x(3)^2)/2) + (c1/(2*m))*x(1)^2 -(E/m))*x(3) - (c1/m)*x(1) + k*(x(2)-x(1));
xprime(4)= -(eta2(i)/m)*x(4) - (c2/m)*x(2) + k*(x(1)-x(2));
xprime = xprime(:);
    end

P(j) = (1/100)*eta1(i)*x(4,j)^2;
P2(j) = (1/100)*eta2(i)*x(4,j)^2;

end
figure(j);
hold on;
plot(eta1,P,eta2,P2); 
xlabel('\eta')
ylabel('Power')
title('Power vs. \eta')
end

[Image Analyst]

http://www.mathworks.com/matlabcentral/answers/13205-tutorial-how-to-format-your-question-with-markup

[tk27182]

Another way for me to phrase this is that I'm trying to plot a function that has a changing variable.

Answer 1

[Chad Greene]

What are your x and t values?

[tk27182]

I call this function into ode45 so that

[t,x] = ode45(@dcoupledeta,tspan,x_int)

[Chad Greene]

We need some numbers to work with, and the ode45 line throws an error without tspan. From your question, I have some suspicions about what the problem might be, but I need to be able to replicate the problem to be sure. What values of x and t are you putting into dcoupledeta(t,x)?