Re: Fitting a bolus passage with gamma variate in IDL??

[Craig Markwardt <craigmnet(at)cow.physics.wisc.edu>]

"Sean Heukels" <sean77=cuthere=@dds.nl> writes:
> Hello all.
> 
> Has someone run into having to fit a
> bolus passage through a vein??
> You need a mono-exponential extrapolation fit.
> I heard that gamma variate fit would be the best.
> 
> But is there someone out there that did
> something like this and wouldn't mind sharing some knowledge?
> How can this be done in IDL?
> And where do I start?

Hello Sean--

I think few of us on this newsgroup are familiar enough with medical
terminology to provide a competent answer to your question.

However, performing curve fitting is fairly straightforward in IDL.
There are a number of standard library routines (CURVEFIT being the
most popular), and I provide a curve fitting routine on my web page
which is a tad easier to use, and is a bit more stable (MPFIT and
drivers).

You must still provide the fitting function.  I thought I understood
what you meant when you said "mono-exponential," but then you go on to
talk about gamma variates.  IDL does have a lot of special functions
in its standard library.  Suffice to say, if you can provide the
parameterized curve, IDL can fit it.

Craig

P.S. Web page at http://cow.physics.wisc.edu/~craigm/idl/idl.html

-- 
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Craig B. Markwardt, Ph.D.         EMAIL:    craigmnet@cow.physics.wisc.edu
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