I am receiving an Error using plot

I am getting this error when running my code

Error using plot

Data must be numeric, datetime, duration, categorical, or an array convertible to double.

Error in pendulun (line 27)

plot(t,y1, t,y2)

m1 = 49/1000;
m2 = 31/1000;
l1 = 0.5;
l2 = 0.5;
M = 1; % mlower/ m upper
l = 100/100; %lu/ l lower
A = (-9.8/1.0)*[(-(l + M*l +M)) M ; 1 -1]; % g/ l lower
w = eig(A);
[Aa,Bb] = eig(A);
omg = sqrt(w);
fre = omg/(2*pi);
nA = 1* A;
%nA = [2 -1; -1 2];
wn = eig(nA);
[S, V]= eig(nA);
syms x(t)
coslam = [(cos(sqrt(V(1,1))*t)) 0 ; 0 (cos(sqrt(V(2,2))*t))];
sinlam = [(sin(sqrt(V(1,1))*t)) 0 ; 0 (sin(sqrt(V(2,2))*t))];
Solu = (S*coslam*(inv(S))*[1/100 ;1/100]) + (S* sinlam* (sqrtm(inv(V)))*(inv(S))*[0;0]);
hold on
t = linspace (0,10,1000000);
y1 = Solu(1);
y2 = Solu(2);
plot(t,y1, t,y2)
title (['Plot of y_{1}(t) and y_{2}(t) of the pendulum' ...
    ' l2 = 1m, M =0.6327, L= 1'])
grid
xlabel ('Time (s)')
ylabel('Distance(m)')
legend('y1(t)','y2(t)')

Answer 1

[Star Strider]

Use the matlabFunction function, evaluate it with ‘t’ and then plot —

m1 = 49/1000;
m2 = 31/1000;
l1 = 0.5;
l2 = 0.5;
M = 1; % mlower/ m upper
l = 100/100; %lu/ l lower
A = (-9.8/1.0)*[(-(l + M*l +M)) M ; 1 -1]; % g/ l lower
w = eig(A);
[Aa,Bb] = eig(A);
omg = sqrt(w);
fre = omg/(2*pi);
nA = 1* A;
%nA = [2 -1; -1 2];
wn = eig(nA);
[S, V]= eig(nA);
syms x(t)
coslam = [(cos(sqrt(V(1,1))*t)) 0 ; 0 (cos(sqrt(V(2,2))*t))];
sinlam = [(sin(sqrt(V(1,1))*t)) 0 ; 0 (sin(sqrt(V(2,2))*t))];
Solu = (S*coslam*(inv(S))*[1/100 ;1/100]) + (S* sinlam* (sqrtm(inv(V)))*(inv(S))*[0;0]);
Solufcn = matlabFunction(Solu)

Solufcn = function_handle with value:
    @(t)[cos(t.*5.7844008256047).*5.0e-3+cos(t.*2.395977272167595).*4.999999999999999e-3;cos(t.*5.7844008256047).*(-2.071067811865475e-3)+cos(t.*2.395977272167595).*1.207106781186547e-2]

hold on
t = linspace (0,10,1000000);
Solv = Solufcn(t)

Solv = 2×1000000

0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100 0.0100

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y1 = Solv(1,:);
y2 = Solv(2,:);
plot(t,y1, t,y2)
title (['Plot of y_{1}(t) and y_{2}(t) of the pendulum' ...
    ' l2 = 1m, M =0.6327, L= 1'])
grid
xlabel ('Time (s)')
ylabel('Distance(m)')
legend('y1(t)','y2(t)')

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[Ibraheem]

thank you very much

[Star Strider]

As always, my pleasure!