RK2:
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Second order Runge-Kutta. Called function is of the form:
Fun(x,{t,p1,p2,...})
Accepts optional arguments that are passed through to Fun.
Time is also optional.
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Form:
x = RK2( Fun, x, h, t, varargin )
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Inputs
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Fun Function Fun(x,{t,...})
x State (column vector)
h Independent variable step
t Current time
varargin Optional arguments
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Outputs
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x Updated state
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Children:
