Euler method

Your opinions of this short paper would be appreciated.
Abstract: The Euler method when properly implemented is a 2nd order
method and is time-reversible.
Full paper is at http://www.properwebsites.co.uk/space/euler.htm
Is its conclusion...
1. Correct and not commonly known.
2. Correct but already commonly known.
3. Wrong.
Thanks

"khufu" wrote in message
...
Your opinions of this short paper would be appreciated.
Abstract: The Euler method when properly implemented is a 2nd order
method and is time-reversible.
Full paper is at http://www.properwebsites.co.uk/space/euler.htm
Is its conclusion...
1. Correct and not commonly known.
2. Correct but already commonly known.
3. Wrong.
Thanks

1 with a but. It looks to be correct... but I doubt this particular 'time
reversible Euler eqn' is well known in itself, although people would
understand what it does. Because it claims to be time reversible, this means
if you run it forwards and get an answer, then run this answer back through
the loop with h - -h, you should get your original p0 and v0 back again. I
haven't tested or proved this, but if you can implement the algorithm, you
should be able to test it, and check that the simpler methods don't work
like this.