Not enough input arguments
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i get this error and I don't know why
Answers (2)
Star Strider
on 6 May 2023
Edited: Star Strider
on 6 May 2023
The ode45 call needs to be —
[t,y] = ode54(@(t,y)assignment(t,y,u,d), tspan, ic)
where ‘u’ and ‘d’ have previously been defined and are present in the calling function workspace.
EDIT — (6 May 20213 at 17:36)
Your ‘assignment’ function apppears to be intended as an ODE function that would be input to one of the differential equation integrators, such as ode45. If so, my approach here should work.
The ODE integrator function will provide the ‘t’ and ‘y’ variables (initially from the ‘tspan’ and ‘ic’ arguments, respecively). It will then calculate subsequent values to evaluate and integrate the ‘assignment’ function.
To illustrate —
u = @(t) sin(2*pi*t/5); % Create Missing Function
d = @(t) cos(2*pi*t/10); % Create Missing Function
[t,y] = ode45(@(t,y)assignment(t,y,u,d), [0 25], 0); % Integrate 'assignment'
figure
plot(t,y)
grid
xlabel('Time')
ylable('y(t)')
title('‘assignment’ Integrated')
function dydt = assignment(t,y,u,d)
dydt = zeros(1,1);
dydt = (-1/5)*y(1) + (0.35/5)*u(t) + d(t)/5;
end
Make appropriate changes to get the desired result.
.
Image Analyst
on 6 May 2023
You probably jsut clicked the green Run triangle on the tool ribbon without actually assigning anything for t, y, u, and d. Assign those FIRST, then run your function from the command window passing in the variables.
t = whatever
y = whatever
u = whatever
d = whatever
dydt = assignment(t,y,u,d)
1 Comment
Abdulelah AlQahtani
on 6 May 2023
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