similar to: Error in eco-model

Hello, I have a syntactic problem with ode. How do I specify vectors of equations in ordinary differential equation systems. (i.e. in my case I want to simulate an a priory undefined number of species that have different parameters but the same behaviour) I demonstrate this using the Lotka Volterra example. The code below does not work and I have not a good idea how to specify this right. ##

Hello, I am an R newbie, trying to use lsoda to solve standard Lotka-Volterra competition equations. My question is: how do I pass a parameter that varies with time, like say, phix <- 0.7 + runif(tmax) in the example below. # defining function lotvol <- function(t,n,p){ x <- n[1]; y <- n[2] rx <- p["rx"]; ry <- p["ry"] Kx <-

I am running R 1.2.3 with ESS5.1.18 with Windows 98. I am trying to use lsoda in the odesolve apckage and am having problems. Question: The return value of the function of the system of ode's has to be a list that includes first, the ode's and second, "a vector (possibly with a `names' attribute) of global values that are required at each point in `times'." I

Hello there, Suppose you want to solve the following system of ODE's (a simple Lotka-Volterra predator prey model) dP/dt = beta*P*V - mu*P dV/dt = r*V - beta*P*V where P and V are the numbers of predators and prey. Now, this is easy to do, but suppose you have a system of equations like this, dP1/dt = beta1*P1*V1 - mu1*P1 dP2/dt = beta2*P2*V2 - mu2*P2 dV1/dt = r1*V1 - beta1*P1*V1

dear all. Would someone be kind and willing to explain the code below for a person who has never used R? ( that is if one has enough time and inclination) It implements gillepsie's stochastic algorithm for Lotka Volterra model. What would help me tremendously is to see the breakdown of the line by line code into plain english. thanks for any insights or other comments. sean

I have a dataframe of animal locations that I need to have in incremental order so that I can calculate the distance traveled between each time step. However, I have identified a few values that don't seem to sort properly. For instance, the last value in the table below should be the first value after sorting, since its time value is '00:01:35'. But, for some reason, it seems to be

I've seen a few threads about this, but none that seem to answer my problem I have a list of .txt files in a directory that I am reading into R and row binding together. I am using the following code to do so: # Directory where files are found my.txt.file.directory <- "C:/Jared/Data/Kenya/Wildebeest/Tracking_Data" names.of.txt.files <-

Does anyone know of example r-code/packages for carrying out analysis? Preferably this would have examples from real experimental data of two or more competing species... Thanks Chris Buddenhagen [[alternative HTML version deleted]]

Dear All! It's now weeks that I'm going crazy with R, and as I'm a new user I now ask for help (also because I still have only a few days to finish..)... So shortly I describe you my Experiment in which I was looking for the decomposition of herbivore dung under different treatments: I made a box design experiment which is structured in the following way: I collected dung from 2

I have tried to print a table of greek alphabet names and symbols without success. I can print one character at a time but can't seem to find a way to automate an entire list of the symbols. Some of the code I have tried is below. I have searched on help, worked the examples in the December 2002 R Help Desk article and plotmath but have not been able to find a way to accomplish the

On 5 June 2018 at 16:23, <dag at cray.com> wrote: > The name "getSizeExpressionInBits" makes me think that a Value > expression will be returned (something like a ConstantExpr that uses > vscale). I would be surprised to get a pair of integers back. Same here. > If we went the ConstantExpr route and added ConstantExpr support to > ScalarEvolution, then SCEVs

Dear Sirs, I wrote a patch for pdbedit (pdb_xml.c) which handles cases with national alphabet characters in GECOS fields. I sent it directly to Jelmer Vernooij, but there was no answer. Who can review the supplied patch ? Cheers, Ilia Chipitsine -------------- next part -------------- --- pdb_xml.c.orig Tue Aug 31 12:12:02 2004 +++ pdb_xml.c Tue Aug 31 12:12:07 2004 @@ -373,6 +373,7 @@

https://bugs.freedesktop.org/show_bug.cgi?id=107431 Bug ID: 107431 Summary: Crash system Product: Mesa Version: 18.0 Hardware: x86-64 (AMD64) OS: Linux (All) Status: NEW Severity: critical Priority: medium Component: Drivers/DRI/nouveau Assignee: nouveau at

Hi everybody, I'm using Windows XP Prof, R 2.5.1 and a Pentium 4 Processor. Now, I want to solve a quadratic optimization program (Portfolio Selection) with the quadprog package I want to minimize (\omega'%*%\Sigma%*%\omega) Subject to (1) \iota' %*% \omega = 1 (full investment) (2) R'%*%\omega = \mu (predefined expectation value) (3) \omega \ge 0 (no short sales). Where

Dear useRs, A new version of the package GillespieSSA (0.3-1) has been uploaded to CRAN. The GillespieSSA package (Gillespie's Stochastic Simulation Algorithm) provides a simple to use, versatile, and extensible interface to a number of Monte Carlo implementations of the stochastic simulation algorithm (SSA) and is intended for scientists, teachers, and students alike. The SSA is a

Dear useRs, A new version of the package GillespieSSA (0.3-1) has been uploaded to CRAN. The GillespieSSA package (Gillespie's Stochastic Simulation Algorithm) provides a simple to use, versatile, and extensible interface to a number of Monte Carlo implementations of the stochastic simulation algorithm (SSA) and is intended for scientists, teachers, and students alike. The SSA is a

On Jul 30, 2009, at 12:09 AM, Chris Lattner wrote: > Hi All, > > I'm happy to announce that Apple has agreed to let llvm.org (and > anyone else) use the great LLVM logo they designed for WWDC. If > you're interested, you can see the full version of the logo on this > page: > http://llvm.org/Logo.html > > I personally think that this is a pretty great

I have read just the comment from Mark Wielaard, the leader of GNU Classpath: http://gnu.wildebeest.org/diary/index.php?p=129 And after that I have a question, if somethinl like Mauve exists also for WINE/ReactOS? GNU Classpath is a OpenSource-Version of the Java Standard Edition Classes. And Mauve are testclasses, which test, that the OpenSource JVMs with GNU Classpath are still working

I have a series of animals that are being radio-tracked. I have written some code that goes through each animal and calculates the total distance that each animal is traveling. I will need to run these data on a regular basis and want to write the result to a .php webpage file so that the page updates automatically when I re-run the code. I thought I'd be able to use the

While it was a good move from Rails part to escape ERB <%= %> tags by default, it doesn''t seem to happen to Sprockets as well. The strange bit is that according to Sprockets documentation, it would be just a matter of naming your template as .jst.eco to enable Eco: https://github.com/sstephenson/sprockets#javascript-templating-with-ejs-and-eco Then, extracted from Eco