Forming a matrix using Euler's method and ODE

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The discussion focuses on using Euler's method to form a matrix from a given operator L, defined as Lx = x'(t) + u(t)x(t) = 0, with initial conditions x(t0) = x0. Participants clarify that Euler's method is expressed as x(t_{n+1}) = x(t_n) + Δt f(x_n, t_n), where f represents the derivative x'(t_n). The equation is manipulated to show that x'(t) can be expressed as -u(t)x(t). By substituting this back into the original equations, the necessary transformations for matrix formation are outlined. The conversation emphasizes the importance of correctly applying Euler's method to derive the matrix representation.
jaobyccdee
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L is the operator. Lx=x'(t)+u(t) x(t) =0. Provided that x(t0)=x0.
Before writing the matrix. The book express it out in equations.
x(t0)==x0
x(t1)-x(t0)+Δt u(t0) x(t0)==0
x(t2)-x(t1)+Δt u(t1) x(t1)==0
...
Euler's method is x(t0)+Δt f[x0,t0], right?
so where did the x'(t) from the original ODE goes?
 
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Hi jaobyccdee! :smile:

Euler's method is x(t_{n+1}) = x(t_n) + \Delta t f(x_n, t_n), where f(x_n, t_n) = x'(t_n).

With Lx=x'(t)+u(t) x(t) =0, it follows that x'(t)=-u(t) x(t).

Substitute, rewrite the equation, and your equations should follow...
 
Thx!:)
 
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