Error report when using ode45 function

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The following errors occurred in solving the tripartite evolutionary game,does anyone know the reason?
Here is the error.
索引超出矩阵维度。
出错 differential (line 2)
dxdt=[x(1)*(1-x(1))*(10-3*x(3)-5*x(2));x(2)*(1-x(2))*(4*x(1)+12.6*x(3)-9);
出错 odearguments (line 87)
f0 = feval(ode,t0,y0,args{:}); % ODE15I sets args{1} to yp0.
出错 ode45 (line 115)
odearguments(FcnHandlesUsed, solver_name, ode, tspan, y0, options, varargin);
出错 run (line 5)
[T,Y]=ode45(@differential,[0,20],[i j m]);
The code is as follows.
function dxdt=differential(x,t)
dxdt=[x(1)*(1-x(1))*(10-3*x(3)-5*x(2));x(2)*(1-x(2))*(4*x(1)+12.6*x(3)-9);
x(3)*(1-x(3))*(3*x(1)*x(2)+20.4*x(2))]
%t是演化的步长和时间
end
--------------------------------------
clear all
for i=0.1:0.2:0.9
for j=0.1:0.2:0.9
for m=0.1:0.2:0.9
[T,Y]=ode45(@differential,[0,20],[i j m]);
figure(1)
grid on
plot(T,Y(:,1),'r-','lineWidth',1);
hold on
plot(T,Y(:,2),'b--','lineWidth',1);
hold on
plot(T,Y(:,3),'g*','lineWidth',1);
hold on
end
end
end
  2 Comments
James Tursa
James Tursa on 20 Feb 2021
Please delete these images and instead post your code and error messages as text highlighted with the CODE button. We can't copy & run pictures.
Erin Sausage
Erin Sausage on 21 Feb 2021
Oh thanks for reminding me. I re-edit the post as you say, if possible, could you plz help me to see why such the error occurs?

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Accepted Answer

Walter Roberson
Walter Roberson on 21 Feb 2021
function dxdt=differential(x,t)
needs to be
function dxdt=differential(t,x)
  3 Comments
Walter Roberson
Walter Roberson on 21 Feb 2021
No, versions would not have anything to do with it. The code was just wrong. In order to use that function the way it was, you would need to use
[T,Y]=ode45(@(t,x)differential(x,t), [0,20], [i j m]);
Erin Sausage
Erin Sausage on 21 Feb 2021
I see. I'm so greatful for your reply!

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