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Re: ODE's again (sorry)
- From: "Sam Halliday" <plendily at hotmail dot com>
- To: gsl-discuss at sources dot redhat dot com
- Date: Sat, 02 Mar 2002 20:39:55 +0000
- Subject: Re: ODE's again (sorry)
- Bcc:
ok (sorry about all these posts),
about the runge-kutta...
it wouldnt be that the so called 'initial value of dy/dt' (first appearance
of y[1] in main() in the example of chapter 25) is in actual fact the value
dy/dt at (t +/- 0.25*tstep) and NOT at the initial 't'?... this would solve
why im getting the discontinuity. and if this is so... is there any way i
can pass dy/dt at 't'? and also, should this not be how the function should
be called?
i have comfirmed by the euler method that the calculation when solving for a
large range is correct. although there is always a discrepency in the second
calculated dy/dx value when solving just one predicted 'y' value and
reinserting values back into the call. is there no way to call rk4 to just
solve the next value, then reinsert.. without this discrepency?
cheers,
Sam
---
ignore the tripe that follows:
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