R help - Oct 2009 - Solving a nonlinear System of equations

Hello there,

I wish to solve the following nonlinear System of equations:

+ u1 - Vmax11*S1/(S1 + Km11 *(1 + S2/Km21)) - Vmax12*S1/( S1 + Km12
*(1+S2/Km22)) == 0
+ u2 - Vmax22*S2/(S2 + Km22 *(1 + S1/Km12)) - Vmax21*S2/( S2 + Km21
*(1+S1/Km11)) == 0
+ Vmax11*S1/(S1 + Km11 *(1 + S2/Km21)) + Vmax12*S1/( S1 + Km12 *(1+S2/Km22)) -
d1*P1 == 0
+ Vmax22*S2/(S2 + Km22 *(1 + S1/Km12)) + Vmax21*S2/( S2 + Km21 *(1+S1/Km11)) -
d2*P2 == 0

S1, S2, P1, P2 are the Variables, 
u1, u2, Vmax11, Vmax12, Vmax21, Vmax22, Km11, Km12, Km21, Km22, d1 and d2 are
Parameters which are given before the solving is attempted. My intention/endgame
is to vary 2 or more of the Parameters and obtain a heatmap out of the resulting
stationary points.



Best Wishes, 

Andrej Schmelzer

                    
                 
                 

-- 

http://portal.gmx.net/de/go/dsl02

There are two packages for solving nonlinear systems:  one is the `BBsolve'
function in the "BB" package, and the other is `nleqslv' in the
"nleqslv" package.


Ravi.  
____________________________________________________________________

Ravi Varadhan, Ph.D.
Assistant Professor,
Division of Geriatric Medicine and Gerontology
School of Medicine
Johns Hopkins University

Ph. (410) 502-2619
email: rvaradhan at jhmi.edu


----- Original Message -----
From: Andrej Iljitsch Schmelzer <andrej-i-schmelzer at gmx.de>
Date: Sunday, October 11, 2009 6:18 pm
Subject: [R] Solving a nonlinear System of equations
To: r-help at r-project.org

> Hello there,
> 
> I wish to solve the following nonlinear System of equations:
> 
> + u1 - Vmax11*S1/(S1 + Km11 *(1 + S2/Km21)) - Vmax12*S1/( S1 + Km12 
> *(1+S2/Km22)) == 0
> + u2 - Vmax22*S2/(S2 + Km22 *(1 + S1/Km12)) - Vmax21*S2/( S2 + Km21 
> *(1+S1/Km11)) == 0 
> + Vmax11*S1/(S1 + Km11 *(1 + S2/Km21)) + Vmax12*S1/( S1 + Km12 
> *(1+S2/Km22)) - d1*P1 == 0
> + Vmax22*S2/(S2 + Km22 *(1 + S1/Km12)) + Vmax21*S2/( S2 + Km21 
> *(1+S1/Km11)) - d2*P2 == 0
> 
> S1, S2, P1, P2 are the Variables, 
> u1, u2, Vmax11, Vmax12, Vmax21, Vmax22, Km11, Km12, Km21, Km22, d1 and 
> d2 are Parameters which are given before the solving is attempted. My 
> intention/endgame is to vary 2 or more of the Parameters and obtain a 
> heatmap out of the resulting stationary points.
> 
> 
> 
> Best Wishes, 
> 
> Andrej Schmelzer
> 
>                     
>                  
>                  
> 
> -- 
> 
> 
> 
> ______________________________________________
> R-help at r-project.org mailing list
> 
> PLEASE do read the posting guide 
> and provide commented, minimal, self-contained, reproducible code.