similar to: nlmeODE package combining NLME with a differential equation solve r

Dear Colleagues, Our group is also working on implementing the use of R for pharmacokinetic compartmental analysis. Perhaps I have missed something, but > fit <- nls(noisy ~ lsoda(xstart, time, one.compartment.model, c(K1=0.5, k2=0.5)), + data=C1.lsoda, + start=list(K1=0.3, k2=0.7), + trace=T + ) Error in eval(as.name(varName), data) : Object

Dear R-helpers, I have some problem with a model I am trying to run with nlmeODE. I have a covariate that I want to include in the model and I can't find in the documentation how to include it in the model so that it can calculate it. >formula(trial) PME ~ time | Ident abcnoniso <- list(DiffEq=list( debdt = ~ -ksol*pH*eb , desdt = ~

I am trying to use nlmeODE. But I don't know what is ObsEq. How you can get it from your ODEs system? Could someone help me out? Best, Ron

[reported originally by Christoffer Tornøe] > f <- ordered(month.name) > f [1] January February March April May June July [8] August September October November December 12 Levels: April < August < December < February < January < July < ... < September > unique(f) [1] January February March April May June July

Dear all, I have two questions: 1. Does anyone know if nlmeODE package will work once odesolve is discontinued? If i understand well nlmeODE depends on odesolve. 2. Can anyone suggest another package I could use to fit complex PKPD models (described using differential equations) to data? Thanks a lot! Magdalena

The Fraunhofer Institute for Industrial Mathematics ITWM in Kaiserslauern, Germany, is looking for a researcher in its department for Financial Mathematics, starting as soon as possible. We are a team working in the following domains of research and industrial projects: Development of models and algorithms for pricing of financial derivatives; evaluation, optimization and risk assessment of

Hello, I want to know if there are some functions or packages to solve differential and integral equation using R. Thanks. Shao chunxuan. [[alternative HTML version deleted]]

Greetings, I've setup a samba server (ver 3.0.14a-3) on debian sarge. When I copy files to the server, the 'date created' attribute is always the same value as the 'date modified' attribute. The 'date modified' attribute remains the same, but the 'date created' changes as noted above. I also have a snap server which has the same type of behavior. It is my

Hello! I would like to know if R can solve Differential Equations... I don't think so because, in my point, I see R like a Statistical System, not a Math System. Am I wrong? Thank you very much. M??rcio de Medeiros Ribeiro Graduando em Ci??ncia da Computa????o Departamento de Tecnologia da Informa????o - TCI Universidade Federal de Alagoas - UFAL Macei?? - Alagoas - Brasil Projeto CoCADa

Dear all, I wonder if there is a way to specify a model in differential equations for nlme(). Or in other packages? Appreciate any comment. Thanks. Jun Shen [[alternative HTML version deleted]]

Hello list I have a theoretical differential equation model (two coupled differential equations) describing the acidification of dairy cultures in milk: dX/dt = f(H, param)*X dH/dt = g(param)*dX/dt pH = -log10(H) I also have actual data of the same. I would like to estimate the parameters of the theoretical model from real data, but don't know how to go about it in R (I'm fairly new

Dear Michael, One key is adjustment of nls optimizer tolerance. I notice it has to be higher than usual, but, I recovered your noisy "known" parameter values with an error of K1 (-7%) and k1 (-6%): #### Miller problem with Dalgaard modifications ## Linares 1/22/2004 ## Solution 1 nls(noisy ~ lsoda(xstart, time, one.compartment.model, c(K1=K1, k2=k2))[,2], data=C1.lsoda,

Dear R-Users, I would like to know whether it is possible to draw several stacked barplots (i.e. side by side on the same sheet)... my data look like : Cond1 Cond1' Cond2 Cond2' Compartment 1 11,81 2,05 12,49 0,70 Compartment 2 10,51 1,98 13,56 0,85 Compartment 3 1,95 0,63 2,81 0,22 Compartment 4 2,08 0,17

Dear all, I have a Pharmokinetics data set where single dose is used for several time points on 8 subjects. I wanted to fit a two compartment model on the data set to see whether it is reasonable. This is the first time to analyze a PK data set and am not familar with various concepts in the compartment models. It seems that PK.fit function in the PK.fit package can be used to fit

> >For example (and this is only an example), a private namespace may be >assigned for each user at login time (at the level of the login shell). >Thus, the user''s "ls" commands see files in whatever directory the >private namespace is rooted, and for all intents and purposes it appears >to be an ordinary filesystem. Yet no other users can see this. User runs

Hi there LARTC, We are running a set of three systems for semiconductor technology, and would like to finalize our work in getting them to interoperate properly, but have run into some issues that touch on the very fabric of TCP/IP expertise. Iptables has already been used to solve "part of this", can we somehow use Diffserv capabilities to acheive the aims of modfiying packets such

i am trying to solve a partial differential equation analytically(PDE) in R . i have found some functions that do the stuff numerically. But that will not meet my purpose. is there any function to solve PDE analytically. please help. -- View this message in context: http://r.789695.n4.nabble.com/analytical-solution-of-partial-differential-equation-tp4291618p4291618.html Sent from the R help

Hello, I am having troubles with heat conduction problem. Below is the given information. Should I move forward with this problem like any other 1-D PDE? ?T/?t = a* (?^2T/?x^2) I.C. For t = 0 and 0 ? x ? 10, T = 0 ?C B.C. For x = 0 cm and all t , T = 100?C For x = 10 cm and all t , T = 0 ?C The thermal diffusivity is a = 2.0 cm^2 /s. I also added what I have for code in R. Any help will

I'm trying to write differential equations into R code. Can anyone help me with the following equation: (dy/dt) = v (dv/dt) = y - y^3 + c(sin t) where c is a constant. I've been using the "deriv()" function and it seems to work out the best, but I'm having trouble converting the above formula to R code. Thank you, Tim Sharac Sign up for Internet Service under $10

I am an initial user of R. Could you give me some explanations or examples on how to solve the first order differential equations by the first-order Runge-Kutta method? Thank you very much Kind regards