MathGroup Archive 1996

[Date Index] [Thread Index] [Author Index]

Search the Archive

Derivatives of InterpolatingFunctions


I'm using an InterpolatingFunction to model a set of data that is a
function of three variables (range,height,frequency).  I need to
generate the partial derivatives of this InterpolatingFunction with
respect to each of the variables.  Unfortunately, version 2.2 of
Mathematica appears unable to do this, unless the
InterpolatingFunction is a function of only one variable.

My questions are:

I know I could approximate the derivative using something along the
lines of (f[x+dx,y,z]-f[x-dx,y,z])/(2dx), but I suspect that this
could lead to problems if I make the wrong choice of dx.  Does anyone
care to comment?

Many thanks,

Paul


__________________________________________________________

Paul E Howland, MEng CEng MIEE         Tel +44-1684-895767
Long Range Ground Radar Sensors        Fax +44-1684-896315
DRA Malvern
Malvern, Worcs, UK
__________________________________________________________



  • Prev by Date: Re: Light Propigation Code
  • Next by Date: Re: file name as mathematica function parameter
  • Previous by thread: Re: Why no solution to 3 eqns. in 3 unk. ?
  • Next by thread: Re: Derivatives of InterpolatingFunctions