Matlab[ode45] - use MATLAB(R) to solve a previously defined system, f, with ODE45
Matlab[ode15s] - use MATLAB(R) to solve a previously defined system, f, with ODE15s
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Calling Sequence
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ode45(f, Trange, IC)
ode45(f, Trange, IC, tol=Tol)
ode15s(f, Trange, IC)
ode15s(f, Trange, IC, tol=Tol)
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Parameters
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f
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string naming a function defined in MATLAB
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Trange
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range, t_initial..t_final
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IC
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initial conditions vector; for example, [0, 0, 0]
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tol=Tol
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optional floating-point setting for tolerance (default is .001)
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Description
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The ode45 command uses MATLAB to compute the ODE45 solution of a differential system. The ode15s command uses MATLAB to compute the ODE15S solution of a differential system.
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To be valid, the call must name the function (f) defined in MATLAB, and specify both the time range (Trange) and the initial condition vector (IC).
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The function f must either be a built-in MATLAB function, or a function defined in the file f.m in the active MATLAB path
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The time range must contain both a start time (t_initial) and an end time (t_final).
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The initial condition (IC) must have a dimension consistent with the dimension of the system defined in the function, f.
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The tolerance option (specified using 'tol'=Tol) must be a floating-point value. It defaults to .001 if not specified.
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Executing the ode45 command returns two Vectors: (T, X). T is the Vector of time steps where f was evaluated, and X is a Vector of values of f, evaluated at times in T.
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Examples
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Call ode45 to work on a built-in MATLAB function.
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Call ode15s to work on a built-in MATLAB function.
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Create a user-defined function, rocket, in Maple. The file may also be predefined in the current path.
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Use the ssystem command to set the permissions on UNIX systems.
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Open the Matlab link.
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Before accessing the user-defined function, the file needs to be opened (in MATLAB).
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Set global variables (in MATLAB).
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Setup the problem.
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Solve the problem.
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Plot the results.
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