I’m trying to run the following code, byt I have the error "Error in untitled (line 9) [t,x]=ode45(‘prob’,tspan,x0);" .
Why is that happening? Can anyone help me, please? Thank you!

%Numerical Solutions
%Problem #57
clc
clear
close all
%Numerical Solution
x0=[0;0];
tspan=[0 15];
[t,x]=ode45(‘prob’,tspan,x0);
figure(1)
plot(t,x(:,1));
title(‘Problem #57’);
xlabel(‘Time, sec.’);
ylabel(‘Displacement, m’);
hold on
%Analytical Solution
m=100;
c=20;
k=1000;
F=30;
w=sqrt(k/m);
d=c/(2*w*m);
wd=w*sqrt(1-d^2);
to=1;
phi=atan(d/sqrt(1-d^2));
%for t<to
t=linspace(0,1,3);
x=0.*t;
plot(t,x,’*’);
%for t>=to
t=linspace(1,15);
x=F/k-F/(k*sqrt(1-d^2)).*exp(-d.*w.*(t-to)).*cos(wd.*(t-to)-phi);
plot(t,x,’*’);
legend(‘Numerical’, ‘Analytical’)
%M-file for Prob #50
function dx=prob(t,x)
[rows, cols]=size(x);dx=zeros(rows, cols);
m=100;
c=20;
k=1000;
F=30;
if t<1
dx=0;
else
dx(1)=x(2);
dx(2)=-c/m*x(2) – k/m*x(1) + F/m;
end
endI’m trying to run the following code, byt I have the error "Error in untitled (line 9) [t,x]=ode45(‘prob’,tspan,x0);" .
Why is that happening? Can anyone help me, please? Thank you!

%Numerical Solutions
%Problem #57
clc
clear
close all
%Numerical Solution
x0=[0;0];
tspan=[0 15];
[t,x]=ode45(‘prob’,tspan,x0);
figure(1)
plot(t,x(:,1));
title(‘Problem #57’);
xlabel(‘Time, sec.’);
ylabel(‘Displacement, m’);
hold on
%Analytical Solution
m=100;
c=20;
k=1000;
F=30;
w=sqrt(k/m);
d=c/(2*w*m);
wd=w*sqrt(1-d^2);
to=1;
phi=atan(d/sqrt(1-d^2));
%for t<to
t=linspace(0,1,3);
x=0.*t;
plot(t,x,’*’);
%for t>=to
t=linspace(1,15);
x=F/k-F/(k*sqrt(1-d^2)).*exp(-d.*w.*(t-to)).*cos(wd.*(t-to)-phi);
plot(t,x,’*’);
legend(‘Numerical’, ‘Analytical’)
%M-file for Prob #50
function dx=prob(t,x)
[rows, cols]=size(x);dx=zeros(rows, cols);
m=100;
c=20;
k=1000;
F=30;
if t<1
dx=0;
else
dx(1)=x(2);
dx(2)=-c/m*x(2) – k/m*x(1) + F/m;
end
end I’m trying to run the following code, byt I have the error "Error in untitled (line 9) [t,x]=ode45(‘prob’,tspan,x0);" .
Why is that happening? Can anyone help me, please? Thank you!

%Numerical Solutions
%Problem #57
clc
clear
close all
%Numerical Solution
x0=[0;0];
tspan=[0 15];
[t,x]=ode45(‘prob’,tspan,x0);
figure(1)
plot(t,x(:,1));
title(‘Problem #57’);
xlabel(‘Time, sec.’);
ylabel(‘Displacement, m’);
hold on
%Analytical Solution
m=100;
c=20;
k=1000;
F=30;
w=sqrt(k/m);
d=c/(2*w*m);
wd=w*sqrt(1-d^2);
to=1;
phi=atan(d/sqrt(1-d^2));
%for t<to
t=linspace(0,1,3);
x=0.*t;
plot(t,x,’*’);
%for t>=to
t=linspace(1,15);
x=F/k-F/(k*sqrt(1-d^2)).*exp(-d.*w.*(t-to)).*cos(wd.*(t-to)-phi);
plot(t,x,’*’);
legend(‘Numerical’, ‘Analytical’)
%M-file for Prob #50
function dx=prob(t,x)
[rows, cols]=size(x);dx=zeros(rows, cols);
m=100;
c=20;
k=1000;
F=30;
if t<1
dx=0;
else
dx(1)=x(2);
dx(2)=-c/m*x(2) – k/m*x(1) + F/m;
end
end error untitled MATLAB Answers — New Questions

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