Re: [SOSlib-devel] variable compartment bug[Scanned]

[Andrew F. <af...@ph...>]

Rainer

the complied version will be to be changed as well

yours Andrew=20

> -----Original Message-----
> From: sbm...@li...=20
> [mailto:sbm...@li...] On=20
> Behalf Of Rainer Machne
> Sent: 13 June 2006 11:42
> To: SOSlib Development
> Subject: [SOSlib-devel] variable compartment bug[Scanned]
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> Folks
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> Lukas has identified another serious bug!
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> SOSlib doesn't support variable compartments.
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> We initialize sundials with ODEs for concentrations d[A]/dt,=20
> and sundials calculates [A] + (d[A]/dt)*h, where h is a small=20
> time step and [A] is the initial condition or the current value.
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> If we have a variable, e.g time-dependent compartment, then=20
> d[A]/dt will change with changing compartment because the=20
> compartment size is part of the right hand side.
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> However, not only d[A]/dt is dependent on the volume, but=20
> also [A], i.e.=20
> the current value in data->value!
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> The attached example file exemplifies this.
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> So we actually should use an ODE system in amount/time=20
> instead of concentration/time, and have a second data->value=20
> array for concentrations to be used in formula evaluation.
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> Didn't we discuss this once? I remember that I had started to=20
> do this (ODEs in amount/time), but then it got more=20
> complicated then I thought and something else came up.
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> Can you think of any problems we will run into? Andrew, how=20
> about the compiling version?
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> Rainer
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