Re: InterpolatingFunctionAnatomy.m

*To*: mathgroup at smc.vnet.net*Subject*: [mg57086] Re: InterpolatingFunctionAnatomy.m*From*: Mark Fisher <mark at markfisher.net>*Date*: Sun, 15 May 2005 03:03:40 -0400 (EDT)*References*: <200505120633.CAA08961@smc.vnet.net> <d614l5$ni0$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

All interpolatingfunctionanatomy.m contains is a bunch of "wrapper" defintions for InterpolatingFunction extractors defined within the Context "DifferentialEquations`InterpolatingFunctionAnatomy`". Given an InterpolatingFunction ifun, here is the syntax: ifun@string[] where string is one of the following: "Domain" "Coordinates" "DerivativeOrder" "InterpolationOrder" "Grid" "ValuesOnGrid" For example, one could define InterpolatingFunctionDomain[ifun_InterpolatingFunction] := ifun@"Domain"[] --Mark. Chrisantha wrote: > Dear All, > > Can anyone possible send me the interpolatingfunctionanatomy .m file. I > have Mathematica 5.0 only. I am running a simulation of chemical > kinetics, and need the volume to be changed at each timestep which then > scales the concentrations. This means as far as I am aware that I will > have to use the EventLocator controller. > > In my system of dif equations I have > > > X'[t] = (bla bla ... ) > V'[t] = (k X[t] ) > > At each timestep I need to scale X[t] by the ratio of (V[t]/V[t+1]) > because V is the volume of the cell that the chemical X is in, and X > increases this volume. Therefore, X[t] has to be reduced by a ratio of > the previous volume to the current volume. I can only think of doing > this by having an event detect when the volume increases by a fixed > amount, and catching that event,. and then rescaling X'[t] and > restaring NDSolve from there. I think the EventLocator can do this > automatically. Is there a better way to do this? > > Yours ever, > Chrisantha Fernando > > >

**References**:**Re: calculate de Jong function***From:*"David Park" <djmp@earthlink.net>