similar to: Ask for help with Error: Object not found

Displaying 20 results from an estimated 1000 matches similar to: "Ask for help with Error: Object not found"

2010 Sep 20
1
ERROR: Object not found
Dear All, I am trying to use ode solver "rk4" to solve an ODE system, however, it keeps saying: Error in eval(expr, envir, enclos) : object "dIN" not found. The sample codes are enclosed as follows, please help me. Thank you very much! rm(list=ls()) library(odesolve) # The ODE system ode <- function(t,x,p){ with(as.list(c(x,p)),{
2010 Apr 06
1
estimating the starting value within a ODE using nls and lsoda
All- I am interested in estimating a parameter that is the starting value for an ODE model. That is, in the typical combined fitting procedure using nls and lsoda (alternatively rk4), I first defined the ODE model: minmod <- function(t, y, parms) { G <- y[1] X <- y[2] with(as.list(parms),{ I_t <- approx(time, I.input, t)$y dG <- -1*(p1 + X)*G +p1*G_b dX <-
2004 Jan 22
4
Fitting compartmental model with nls and lsoda?
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
2010 Sep 16
1
More accurate ODE solver?
Dear All, I was using rk4 and lsoda to solve a ODE system. However, both of them gave bad accurate solutions, especially compared with Matlab solver ODE45. For example, ODE45 gave solutions that can go to a stable level (about 1.6) when time goes to infinity, however, the solutions from lsoda are decreasing to very very small (about 1e-130) numbers. Does R have more accurate ODE solvers as
2003 Oct 07
2
freebsd.org mirroring
Hello all, Help me please do mirror of freebsd.org. I got *.sgml through CVSup, installed textproc/docproj. But when I typed make: [root@xxx /www/freebsd/]make ===> en ===> en/security ===> en/commercial ===> en/docproj ===> en/news ===> en/news/1993 ===> en/news/1996 ===> en/news/1997 ===> en/news/1998 ===> en/news/1999 ===> en/news/2000 ===> en/news/2001
2009 Jun 12
2
External signal in ODE written in C (using deSolve and approx1?)
Dear list The deSolve package allows you to specify the model code in C or Fortran. Thanks to the excellent vignette this works fine. However I have not yet managed to use forcing functions in C code. In pure R code this works very well with approxfun() specified outside the model: ############################################### #Model lvml <- function(t, x, parms) {
2004 Jun 10
2
odesolve: lsoda vs rk4
I'm trying to use odesolve for integrating various series of coupled 1st order differential equations (derived from a system of enzymatic catalysis and copied below, apologies for the excessively long set of parameters). The thing that confuses me is that, whilst I can run the function rk4: out <- rk4(y=y,times=times,func=func, parms=parms) and the results look not unreasonable:
2009 Sep 02
2
Configuring Parallel SIP Trunks
Hi, I'm trying to configure 2 parallel sip trunks between 2 boxes. However I seem to have the problem that when making a call from Box 2 to Box 1, it sometimes says authentication failed because it is using the username of the other trunk. Here's my configuration: Box 1: [dp-dp2] type=peer username=dp-dp2 secret=mysecret qualify=yes host=box.2.ip.address context=from-internal [e911-dp2]
2004 Oct 04
3
Beginners problem
Hi, I'm new to R and have a problem with a little test program (see below). Why doesn't <<- in function rk4 assign the new value to y so that it is seen in rktest. I thought that <<- does exactly this. But it seems that I didn't get it right. I would be very appreciative for an explanation of that behaviour of <<-. I know how to write the whole thing so that it
2020 Apr 16
2
Strangeness on X11 screen capture
Hi all, I am running CentOS 7 on a NUC5CPYB. Intel video: 00:02.0 VGA compatible controller: Intel Corporation Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Integrated Graphics Controller (rev 35) When I take a screen shot I get "different" things. I use: export DISPLAY=:0.0 /usr/bin/xwd -silent -root -out screen; convert screen screen.png I tried import also for the screen
2008 Apr 09
3
LSODA not accurate when RK4 is; what's going on?
I'm solving the differential equation dy/dx = xy-1 with y(0) = sqrt(pi/2). This can be used in computing the tail of the normal distribution. (The actual solution is y(x) = exp(x^2/2) * Integral_x_inf {exp(-t^2/2) dt} = Integral_0_inf {exp (-xt - t^2/2) dt}. For large x, y ~ 1/x, starting around x~2.) I'm testing both lsoda and rk4 from the package odesolve. rk4 is accurate using step
2010 May 14
2
Subscripting a matrix-like object
I have an S3 class called "tis" (Time Indexed Series) which may or may not have multiple columns. I have a function "[<-.tis" that I've reproduced below. My question is this: inside of "[<-.tis", how can I distinguish between calls of the form x[i] <- someValue and x[i,] <- someValue ? In either case, nargs() is 3, and looking at the values
2010 May 14
2
Subscripting a matrix-like object
I have an S3 class called "tis" (Time Indexed Series) which may or may not have multiple columns. I have a function "[<-.tis" that I've reproduced below. My question is this: inside of "[<-.tis", how can I distinguish between calls of the form x[i] <- someValue and x[i,] <- someValue ? In either case, nargs() is 3, and looking at the values
2009 May 07
1
data transformation using gamma
Hi R-users, I have this code to uniformise the data using gamma: > length(dp1) [1] 696 > dim(dp1) [1] 58 12 > dim(ahall) [1]  1 12 > dim(bhall) [1]  1 12 > trans_dt <- function(dt,a,b) + { n1 <- ncol(dt) +   n2 <- length(dt) +   trans  <- vector(mode='numeric', length=n2) +   dim(trans) <- dim(dt) +   for (i in 1:n1) +   {  dt[,i] <- as.vector(dt[,i])
2009 May 10
4
Partial Derivatives in R
Quick question: Which function do you use to calculate partial derivatives from a model equation? I've looked at deriv(), but think it gives derivatives, not partial derivatives. Of course my equation isn't this simple, but as an example, I'm looking for something that let's you control whether it's a partial or not, such as: somefunction(y~a+bx, with respect to x,
2006 Mar 26
2
Problem with names() in a plot after ordering a data.frame. Syntax or stupidity?
I am a complete newbie in R . Using R 2.2.0 Windows XP This started as a simple exercise to see if I could produce a simple Cleveland style dotchart with a line from the '2' axis to the dot rather than a continuous line as do "dotchart" and "dotchart2". At least I could not find that option. I got a crude program to work but it includes unnecessary steps.
2011 Aug 20
4
[PATCH 1/2] Make xencommons a bit more idiomatic
Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> diff -r 8d6edc3d26d2 -r cfb49fe940fd tools/hotplug/Linux/init.d/xencommons --- a/tools/hotplug/Linux/init.d/xencommons Sat Aug 13 10:14:58 2011 +0100 +++ b/tools/hotplug/Linux/init.d/xencommons Tue Aug 16 16:56:16 2011 -0700 @@ -29,11 +29,9 @@ XENCONSOLED_PIDFILE=/var/run/xenconsoled.pid shopt -s extglob -if test
2007 Feb 05
2
Exact matching with grep
Hello, I would know if it is possible with grep to match a exact string. For example, I want to match the string "DP2" (and only this) and grep match "DP2BS" too. I have sought in the grep help but I didn't find what I want.
2010 Mar 17
9
[Bug 27136] New: blank screen with G98 [Quadro NVS 420] (NV98) dual GPU, 4-head
http://bugs.freedesktop.org/show_bug.cgi?id=27136 Summary: blank screen with G98 [Quadro NVS 420] (NV98) dual GPU, 4-head Product: xorg Version: 7.5 Platform: x86-64 (AMD64) OS/Version: Linux (All) Status: NEW Severity: normal Priority: medium Component: Driver/nouveau
2012 Dec 04
1
Solve system of equations (nleqslv) only returns origin
I'm solving 4 complex equations simultaneously. Code is below. The code returns only zero's for the solution though there should also be a non-zero result. I'm pretty confident that the equations are correct because they are straight from a published paper and I checked them pretty thoroughly. The parameter values I used are from the published paper as well. Any suggestions for how