Robert,
You can do it using ADVAN9 with NEQUILIBRIUM option in $MODEL, and $AESINITIAL
and $AES blocks. E.g. (where A(13) is what is F in your example) :
$SUBROUTINES ADVAN9 TOL=4
$MODEL NEQUILIBRIUM=1
COMP(COMP1)
....
COMP(COMP13)
$PK
...
$AESINITIAL
INIT = 0; 0=APPROXIMATE, 1=EXACT
A(13)=0.001
$AES
E(13)=A(9)-A(13)-A(13)*A(10)/(KSS+A(13))-A(13)*A(12)/(KSS2+A(13))
$DES
...
$ERROR
Y = A(13)+EPS(1)
Regards,
Katya
--------------------------
Ekaterina Gibiansky, Ph.D.
CEO&CSO, QuantPharm LLC
Web: www.quantpharm.com
Email: [email protected]
Tel: (301)-717-7032
Robert Kalicki wrote:
Dear NMusers,
Most of the models are pre-defined (ADVANx), expressed as a system of
differential equations or provided in the form of an explicit
mathematical equation (PRED).
Is it possible to deal with nonlinear inexplicit equations like y =
f(x,y) where both differential equations and explicit solution equation
are not known or not obvious.
Concretely, using PRED, one would find F on the both sides:
F = f(X) + g(F)
Y = F+EPS(1)
Many thanks in advance
Best regards,
Robert
___________________________________________
Robert M. Kalicki, MD
Postdoctoral Fellow
Department of Nephrology and Hypertension
Inselspital
University of Bern
Switzerland
Address:
Klinik und Poliklinik für Nephrologie und Hypertonie
KiKl G6
Freiburgstrasse 15
CH-3010 Inselspital Bern
Tel +41(0)31 632 96 63
Fax +41(0)31 632 14 58
