## How can I plot this equation?

### Moj (view profile)

on 21 Aug 2013

I want to plot a figure but I don't know how to write "s" string with a loop. Here is my code

```k1=5.3e-12;
k3=7.3e-12;
mu=pi*4e-7;
kapa=9.56e-7;
theta_m1 = 0;
theta_m2 = 0.44;
for theta_m= theta_m1:0.1:theta_m2
fun = @(x)(((k1*cos(x).^2 + k3*sin(x).^2)./(sin(theta_m)^2-sin(x).^2)).^0.5);
s(:) = integral(fun,0,theta_m);
end
```
``` for  theta_m= theta_m1:0.1:theta_m2
hold on
end ```

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### Walter Roberson (view profile)

on 21 Aug 2013
```thetas = theta_m1 : 0.1 : theta_m2
for K = length(thetas)
theta_m = thetas(K);
fun = @(x)(((k1*cos(x).^2 + k3*sin(x).^2)./(sin(theta_m)^2-sin(x).^2)).^0.5);
s(K) = integral(fun,0,theta_m);
end
```

Moj

### Moj (view profile)

on 21 Aug 2013

But why can't this code plot this equation?

Walter Roberson

### Walter Roberson (view profile)

on 21 Aug 2013

Leave out the "for" loop around the plot

```plot((mu/kapa)^0.5 *(2/1e-6)* s(:) ,radtodeg(theta_m))
```

Are you asking why your original code did not plot? It is because you overwrote all of s each time through your loop.

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