Displaying 20 results from an estimated 1000 matches similar to: "R User Group listings"
2010 Feb 17
0
Does the R "statistical language includes, > modules/packages to carry out nonlinear optimization similar to the, > SAS NLIN and NLP procedures?
There is also the OptimizeR project on R-forge
http://r-forge.r-project.org/R/?group_id=395. Other related projects are there also, but
I'll let their authors speak for themselves. Stefan Theussl did a good job in the Task
View, but it is from last June, and it would be a monumental effort to keep up to date
with all the work going on.
We're "almost" ready to put some of our
2011 Nov 18
0
how to define the bound between parameters in nls() (Jinsong Zhao)
The multiple exponential problem you are attempting has a well-known and long history.
Lanczos 1956 book showed that changing the 4th decimal in a data set changes the
parameters hugely.
Nevertheless, if you just need a "fit" and not reliable paramters, you could
reparameterize to k1 and k2diff=k2-k1, so k2=k1+kdiff. Then kdiff has a lower bound of 0,
though putting 0 will almost
2011 Jun 18
2
different results from nls in 2.10.1 and 2.11.1
Hi,
I've noticed I get different results fitting a function to some data on
my laptop to when I do it on my computer at work.
Here's a code snippet of what I do:
##------------------------------------------------------------------
require(circular) ## for Bessel function I.0
## Data:
dd <- c(0.9975948929787, 0.9093316197395, 0.7838819026947,
0.9096108675003, 0.8901804089546,
2013 Feb 19
3
R nls results different from those of Excel ??
Hi all
I have a set of data whose scatter plot shows a very nice power
relationship. My problem is when I fit a Power Trend Line in an Excel
spreadsheet, I get the model y= 44.23x^2.06 with an R square value of 0.72.
Now, if I input the same data into R and use
model< -nls(y~ a*x^b , trace=TRUE, data= my_data, start = c(a=40, b=2)) I
get a solution with a = 246.29 and b = 1.51. I have tried
2010 Nov 16
4
DBLEPR?
Ravi Varadhan and I have been looking at UCMINF to try to identify why it gives occasional
(but not reproducible) errors, seemingly on Windows only. There is some suspicion that its
use of DBLEPR for finessing the Fortran WRITE() statements may be to blame. While I can
find DBLEPR in Venables and Ripley, it doesn't get much mention after about 2000 in the
archives, though it is in the R FAQ
2010 Nov 16
4
DBLEPR?
Ravi Varadhan and I have been looking at UCMINF to try to identify why it gives occasional
(but not reproducible) errors, seemingly on Windows only. There is some suspicion that its
use of DBLEPR for finessing the Fortran WRITE() statements may be to blame. While I can
find DBLEPR in Venables and Ripley, it doesn't get much mention after about 2000 in the
archives, though it is in the R FAQ
2015 Apr 25
2
Title case in DESCRIPTION for package where a word is a function namei
> On 25 Apr 2015, at 13:11 , Prof J C Nash (U30A) <nashjc at uottawa.ca> wrote:
>
> Hendrik pointed out it was the parentheses that gave the complaint.
> Single quotes and no parentheses seem to satisfy R CMD check. Perhaps
> that needs to be in the WRE.
Well, it is in ?toTitleCase:
...However, unknown
technical terms will be capitalized unless they are single
2015 Apr 24
3
Title case in DESCRIPTION for package where a word is a function name
On 24.04.2015 22:44, Ben Bolker wrote:
> Prof J C Nash (U30A <nashjc <at> uottawa.ca> writes:
>
>>
>> I was preparing a fix for a minor glitch in my optimx package and R CMD
>> check gave an error that the title was not in title case.
>
> [snip] to make Gmane happy ...
>
>> I have found
>>
>> A Replacement and Extension of the
2008 Apr 20
1
Guide to Using KVM
Hi all,
Our CentOS Forum contributor, "scottro", has written a guide to using
KVM with CentOS-5.1 and made it available at:
http://home.nyc.rr.com/computertaijutsu/centoskvm.html
He is offering it for us to put on the CentOS wiki. I would be happy
to wikify it and welcome any comments and suggestions. The contents
will be updated as he adds more to his writing.
Akemi
2015 Apr 24
2
Title case in DESCRIPTION for package where a word is a function name
I was preparing a fix for a minor glitch in my optimx package and R CMD
check gave an error that the title was not in title case. It is
A Replacement and Extension of the optim() Function
R CMD check suggests the incorrect form
A Replacement and Extension of the Optim() Function
'Writing R Extensions' suggests single quotes, i.e.,
A Replacement and Extension of the 'optim()'
2012 Apr 28
2
Character string to R object
I've been creating some R tools that manipulate objective functions for optimization. In
so doing, I create a character string with R code, and then want to have it in my
workspace. Currently -- and this works fine -- I write the code out, then use source() to
bring it in again. Example:
cstr<-"jack<-function(x){\n cat(\"Silly x:\")\n print(x) \n }\n"
write(cstr,
2010 Nov 30
5
Minor warning about seq
I spent more time than I should have debugging a script because I wanted
x<-seq(0,100)*0.1
but typed
x<-seq(O:100)*0.1
seq(0:100) yields 1 to 101,
Clearly my own brain to fingers fumble, but possibly one others may want to avoid it.
JN
2008 Jan 22
1
Lattice on FreeBSD
Hi list
I tried to install package lattice on FreeBSD, but install.package()
does not seem to find it in the repositories, even trying different
mirrors. Could it be that lattice package is not available for
FreeBSD?
--
Armin Goralczyk, M.D.
--
Universit?tsmedizin G?ttingen
Abteilung Allgemein- und Viszeralchirurgie
Rudolf-Koch-Str. 40
39099 G?ttingen
--
Dept. of General Surgery
University of
2010 Jun 01
2
MacOS X binary for lme4 not available on CRAN
Dear group,
I have noticed that the MacOS X binary for lme4 is not available on
CRAN at the moment. I am aware that it may be possible to install from
source but I am not very familiar with that procedure and would rather
avoid it. But I need the package for a statistics course next week. So
can anybody give an update about the situation with the MacOS X
binaries? Will it be resolved within the
2005 Aug 24
0
Model forecasts with new factor levels - predict.warn
predict.warn() -- a function to display factor levels in new data
for linear model prediction that do not exist in the
estimating data.
Date: 2005-8-24
From: John C. Nash (with thanks to Uwe Ligges for suggestions)
nashjc at uottawa.ca
Motivation: In computing predictions from a linear model using factors,
it is possible to introduce new factor levels. This was encountered on
a practical
2005 May 25
1
[Fwd: Re: [Fwd: failure delivery]]
I appear to have hit one of the "drop" issues raised in some discussions
a couple of years ago by Frank Harrell. They don't seem to have been
fixed, and I'm under some pressure to get a quick solution for a
forecasting task I'm doing.
I have been modelling some retail sales data, and the days just after
Thanksgiving (US version!) are important. So I created some dummy
2009 Jul 30
2
lattice shingle plot axis annotation
Hello (R-)Experts
I hope someone can help with this problem concerning axis annotation
of a lattice shingle plot. I want a plot with three shingles to
display some laboratory value over time. In the first panel over the
first few days, then in the next panel some months, and in the last
panel some years. In the following minimal example the axis annotation
will be in days, but I'd like to
2011 Nov 30
3
Upgrading R on my EEE PC netbook
I have been successfully been using R on my EEE PC for some while
now. Although it uses Xandros I have been able to install various
pieces of software by pretending that it was Debian etch. Johannes
was kind enough to continue providing binaries on CRAN for a while
but I think I am the only person still living in the past as CRAN
etch is currently stuck at 2.11.0 and I cannot rely on him to
2009 May 01
1
nlminb - Port library codes
Having looked at documentation and codes, I'm still looking to find out
who did the installation of the Port libraries. As I work on
optimization code improvements, there are often choices of settings
(tolerances etc.), and I'd prefer to learn if there are particular
reasons for choices before diving in and making any adjustments.
It is also worth giving credit where it is due. Given
2011 Jun 26
1
Default values in control list of function
In building a function for a package, I'd like to set the defaults in a control list,
e.g.,
makeg<-function(parameters, eps = 1.0e-7, control=list(showwork=TRUE, rubbish=1.0e+101)){
etc.
}
This does not provide showwork or rubbish within the function if control() is not fully
specified. Copying others, I've previously set the control defaults within the function
then matched