MATLAB: Solving second order differential equations with LaPlace Transforms: getting an error when trying to input an initial condition (R2017b) (“error: untitled line”)

buglaplacelaplace transform

This is my code. I am getting an error in
 syms s 
eqn=sym('D(D(y))(t)+D(y)(t)+y(t)=((t+1)^3)*exp(-t)*cos(t)*sin(3*t)');
lteqn=laplace(eqn,t,s)
syms y ;
neweqn=subs(lteqn,{'laplace(y(t),t,s)','y(0)',''D(y)(0)'},{Y,1,0})
% the line above has the error, and the issue is with the 'D(y)(0)' term
ytrans=simplify(solve(neweqn,Y))
y=ilaplace(ytrans,s,t)

Best Answer

The laplace function does not accept initial conditions (as dsolve does).
I requested this as an enhancement several months ago. It has thus far not appeared.
You will have to do coding gymnastics with the subs function to do the necessary substitutions.
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