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Old 12-23-2016, 12:41 PM
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Re: numerical solution of differential equations

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Originally Posted by sspoldi View Post
one forward Euler integration, one backward Euler integration
Vn+1 = Vn + An∙dt;
Xn+1 = Xn + Vn+1∙dt;

Maybe provides some insight: the above is algebraically equivalent to

Vn+1 = Vn + An∙dt;
Xn+1 = Xn + dt∙(Vn+Vn+1)/2 + ½∙An∙dt2


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Old 12-23-2016, 01:31 PM
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Re: numerical solution of differential equations

Quote:
Originally Posted by Ether View Post
Maybe provides some insight: the above is algebraically equivalent to

Vn+1 = Vn + An∙dt;
Xn+1 = Xn + dt∙(Vn+Vn+1)/2 + ½∙An∙dt2
..so counting the constant acceleration term twice in the position calculation mostly offsets not counting the jerk in the velocity calculation..at least in this case.
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