Please how do I get rid of local variables may have been changed to match the globals error?

I this error: Warning: The value of local variables may have been changed to match the globals. Future versions of MATLAB will require that you declare a variable to be global before you use that variable.

Also, I tried to loop over a solver because my function has a varying parameter xi. Please how I do plot a graph for the different parameters on the same figure? For instance, I wanna plot xi = -0.06 and xi=0.001 on the same figure. I have attched my code.

Answer 1

[Torsten]

Can you take it from here for your case ?

f = @(x,a) x.^2 + a.^2;
x = -2:0.01:2;
a = 0:0.1:1;
array = zeros(numel(a),numel(x));
hold on
for i = 1:numel(a)
    array(i,:) = f(x,a(i));
    plot(x,array(i,:))
end
hold off

[University Glasgow]

Thank you. I tried this for v plot:

hold on
for i = 1:numel(xi)
    v(i,:) = v(z, v(end, :));
    plot(z, v(i,:))
end
hold off

But received this: Index in position 1 is invalid. Array indices must be positive integers or logical values.

[Walter Roberson]

z=linspace(0,d,N+1);

Those will not typically be integers, especially since d = 0.0002;

v = [zeros(length(t), 1) y(:,N:(2*N-2)) zeros(length(t), 1)];

The last row of v will start and end with 0

v(i,:) = v(z, v(end, :));

z is not integer, but you are using it as the first index into the 2D array v.

v(end,:) starts and ends with 0, but you are using it as the second index intothe 2D array v.

[University Glasgow]

Please, how do I fix this?

[Walter Roberson]

You do not fix it. You are treating v as if it is a function rather than an array.

Certainly you cannot fix it when there are no comments indicating what you hope to have happen there.

Note also that your right hand side does not involve i so you are calculating the same thing each iteration until you get to the point where v(i,:) and v(z,:) overlap (and which point you change what v(z,:) refers to and so you start storing different values than the iterations where i < min(z) )

[University Glasgow]

Thank you so much. I have been able do that now.