Displaying 20 results from an estimated 1000 matches similar to: "Optimization problem"
2010 Feb 16
1
Does the R "statistical language includes modules/packages to carry out nonlinear optimization similar to the SAS NLIN and NLP procedures?
Hello R folks,
I'm hoping the answer to the question in the subject line.
I have in the past used SAS PROC NLIN and PROC NLP to carry out
nonlinear optimizations. I'm wondering if there is analogous ways for
doing this using R. If so, could someone please point me to some
literature that would help me examine this further?
Thanks very much.
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2005 Jul 14
2
Fwd: Re: East Asian language
---- Original message ----
>Date: Thu, 14 Jul 2005 19:50:41 +0200
>From: Uwe Ligges <ligges at statistik.uni-dortmund.de>
>Subject: Re: [R] East Asian language
>To: Nan Lin <nlin at math.wustl.edu>
>Cc: r-help at stat.math.ethz.ch
>
>Nan Lin wrote:
>
>> Dear all,
>>
>> I just installed R 2.1.1. The installation program
automatically
2004 Oct 07
1
confidence interval for nls
Do I have the right impression that it's currently not possible to
produce confidence intervals for the nls predictions using R?
I had a course were we used SAS PROC nlin and there you could get
intervals for the parameters and the prediction but I do not have access
to SAS.
Would it be difficult to implement, I tried to dig into the help pages
of nls, vcov and nlsModel but I could not
2005 Apr 17
1
nls segmented model with unknown joint points
Hello,
I am interested in fitting a segmented model with unknown joint points
in nls and perhaps eventually in nlme. I can fit this model in sas (see
below, joint points to be estimated are a41 and a41), but am unsure how
to specify this in the nlm function. I would really appreciate any
suggestions or example code. Thanks a lot. -andy
proc nlin data=Stems.Trees;
params b41=-3 b42=1.5
2009 Aug 06
0
donlp2
Dear Sir,
I am working with one example in R donlp2. How I can get the Hessian matrix
from the output.
p = c(10,10)
par.l = c(-100,-100)
par.u = c(100,100)
nlin.l = nlin.u = 2
fn = function(x) {
x[1]^2+x[2]^2
}
dfn = function(x){
c(2*x[1], 2*x[2])
}
attr(fn, "gr") = dfn
nlcon = function(x){
x[1]*x[2]
}
dnlcon = function(x){
c(x[2], x[1])
}
attr(nlcon, "gr") = dnlcon
2007 Jan 16
1
nonlinear regression: nls, gnls, gnm, other?
Hi all,
I'm trying to fit a nonlinear (logistic-like) regression, and I'd like
to get some recommendations for which package to use.
The expression I want to fit is something like:
y ~ A * exp(X * Beta1) / (1 + exp(-(x + X * Beta2 - xmid)/scal))
Basically, it's a logistic function, but I want to be able to modify
the saturation amplitude by a few parameters (Beta1) and shift the
2010 Sep 05
0
cov.unscaled in NLS - how to define cov.scaled to make comparable to SAS proc NLIN output - and theoretically WHY are they different
I am running a 3-parameter nonlinear fit using the default Gauss-Newton
method of nls.
initialValues.L = list(b=4,d=0.04,t=180);
fit.nls.L = nls(
myModel.nlm ,
fData.L,
start = initialValues.L,
control = nls.control(warnOnly = TRUE),
trace=T
);
summary.nls.L = summary(fit.nls.L);
I run the same analysis in SAS proc NLIN.
proc nlin data=apples outest=a;
parms b=4 d=.04 t=180;
model Y =
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
2007 Oct 22
3
Elasticity in Leslie Matrix
Dear R-users,
I would like to calculate elasticities and sensitivities of each parameters
involved in the following transition matrix:
A <- matrix(c(
sigma*s0*f1, sigma*s0*f2,
s, v
), nrow=2, byrow=TRUE,dimnames=list(stage,stage))
The command "eigen.analysis" avaliable in package "popbio" provides
sensibility matrix and elasticity matrix
2011 Jan 27
4
[LLVMdev] recreate optimized clang output
On 26.01.2011, at 04:39, John McCall wrote:
> On Jan 24, 2011, at 10:36 AM, Hendrix_ at gmx.net wrote:
>> I was using "clang -O3 -S -emit-llvm" got some very optimized output.
>>
>> Then I did "clang -S -emit-llvm" (without optimization) and wanted to optimized the code in a
>> separate pass. The llvm program "opt" did not do anything.
2011 Jan 27
0
[LLVMdev] recreate optimized clang output
On Jan 27, 2011, at 12:02 PM, Hendrix_ at gmx.net wrote:
> OK, I am looking for "LTO"/global optimization. So the function definition will remain "somewhere else" (externally), and the optimizer will find in some other module to possibly inline it later on.
>
> I am planning to concat all the *.ll (eg "link" the files) and pass them to the
2009 Jan 17
2
data.frame: how to extract parts
Hi,
I have a problem with the R syntax.
It's perhaps pretty simple, but I don't understand it ...
I can extract a column from a data.frame with the following code for
example ...
b$row1[b$row1 == "male"]
so I see all male-entries.
But I cannot extract all lines of a data.frame depending on this
criterium;
only.male <- b[b$row1 == "male"]
With that, I
2018 Jan 29
2
send specific NDR message for users in certain OU
Hi,
The question can perhaps be made more generic like this:
Can dovecot generate a *specific* NDR (or an autoreply) for accounts
that meet a specific criterium, such as:
- user account was found under OU=to-delete,CN=company...
contrary to the regular location CN=Users,CN=company...
We would like to move to-be-deleted users to this container, before
actually deleting them. That gives us an
2009 Jul 03
2
Simple one
Just a quickly beginner's question.
I wanna find the mean only from the values from a column related to specific
values from another one. Like, theres a 'region' column, i want the mean of
the value on 'profit' column only from "south" sells from 'region' column
--
View this message in context: http://www.nabble.com/Simple-one-tp24329691p24329691.html
Sent
2011 Jan 27
2
[LLVMdev] recreate optimized clang output
On 27.01.2011, at 21:12, Devang Patel wrote:
>
> On Jan 27, 2011, at 12:02 PM, Hendrix_ at gmx.net wrote:
>
>> OK, I am looking for "LTO"/global optimization. So the function definition will remain "somewhere else" (externally), and the optimizer will find in some other module to possibly inline it later on.
>>
>> I am planning to concat all the
2000 Mar 29
2
regularly lattice & neighbors
Dear R-users,
Is there a procedure to identify neighbors in a regular lattice using either a
"rook" or a "queen" criterium? To be more specific, suppose:
My lattice:
1 2 3
4 5 6
7 8 9
"Rook" Neighbors
1 has neighbors 2,4
2 has neighbors 1,3,5
...
5 has neighbors 2,4,6,8
"Queen Neighbors"
1 has neighbors 2,4,5
2 has neighbors 1,3,4,5,6
For each case,
2011 Nov 18
1
Ensuring a matrix to be positive definite, case involving three matrices
Hi,
I would like to know what should I garantee about P and GGt in order to have
F = Z %*% P %*% t(Z) + GGt always as a positive definite matrix.
Being more precise:
I am trying to find minimum likelihood parameters by using the function
'optim' to find the lowest value generated by $LogLik from the function
'fkf' (http://127.0.0.1:27262/library/FKF/html/fkf.html).
The
2009 Apr 06
2
GarchOxFit output
Dear Sirs,
I have a problem with the garchOxFit output. I want to display only
the value of max.like.est and the information criteria. How can I do
that; I enclose a part of GarchOxFit output, which is what I want to
display.
Best regards,
Vasilios Ismyrlis
GarchOxFit output
No. Observations : 1000 No. Parameters : 2
Mean (Y) : -0.05511 Variance (Y) : 1.06869
2011 Jan 27
1
[LLVMdev] recreate optimized clang output
On 27.01.2011, at 21:12, Devang Patel wrote:
>
> On Jan 27, 2011, at 12:02 PM, Hendrix_ at gmx.net wrote:
>
>> OK, I am looking for "LTO"/global optimization. So the function definition will remain "somewhere else" (externally), and the optimizer will find in some other module to possibly inline it later on.
>>
>> I am planning to concat all the
2007 Apr 23
3
Link AD to pre-existing UNIX accounts
I'm trying to use winbindd to enumerate and link AD users to their pre-
existing UNIX accounts. Right now, winbindd creates new "users" for UNIX based
on windows username and groups.
What I can't figure out is how to explicitly map the AD users to their pre-
existing UNIX accounts. I'd like the users to be able to access their UNIX
accounts with their UNIX authentication