Displaying 20 results from an estimated 1000 matches similar to: "maximization help :"
2010 Jul 03
1
Inverting a scale(X)
G'day, All.
I have been trying to trackdown a problem in my R analysis script. I perform a scale() operation on a matrix then do further work.
Is there any way of inverting the scale() such that
sX <- scale(X)
Xprime <- inv.scale(x); # does inv.scale exist?
resulting in Xprime_{ij} == X_{ij} where Xprime_{ij} \in R
There must be some way of doing it but I'm such a newb
2011 Mar 19
2
problem running a function
Dear people,
I'm trying to do some analysis of a data using the models by Royle & Donazio
in their fantastic book, particular the following function:
http://www.mbr-pwrc.usgs.gov/pubanalysis/roylebook/panel4pt1.fn
that applied to my data and in the console is as follows:
> `desman.y` <- structure(c(3L,4L,3L,2L,1L), .Names = c("1", "2", "3",
2011 Jun 16
2
Bayesian Credible Intervals for a Proportion
I am trying to calculate Bayesian Credible Intervals for a proportion
(disease prevalence values to be more specific) and am having trouble using
R to do this. I am working with ncredint() function but have not had success
with it. Please help!
Example:
Positive samples = 3
Total sampled = 10
Prevalence = 0.3
pvec <- seq(1,10,by=1)
npost = dbinom(pvec,10,prob=0.3, log=FALSE)
ncredint(pvec,
2020 Jan 10
2
SUGGESTION: Settings to disable forked processing in R, e.g. parallel::mclapply()
I'd like to pick up this thread started on 2019-04-11
(https://hypatia.math.ethz.ch/pipermail/r-devel/2019-April/077632.html).
Modulo all the other suggestions in this thread, would my proposal of
being able to disable forked processing via an option or an
environment variable make sense? I've prototyped a working patch that
works like:
> options(fork.allowed = FALSE)
>
2011 Apr 09
1
loop and sapply problem, help need
Dear R experts
Sorry for this question
M1 <- 1:10
lcd1 <- c(11, 22, 33, 44, 11, 22, 33, 33, 22, 11)
lcd2 <- c(22, 11, 44, 11, 33, 11, 22, 22, 11, 22)
lcd3 <- c(12, 12, 34, 14, 13, 12, 23, 23, 12, 12)
#generating variables through sampling
pvec <- c("PR1", "PR2", "PR3", "PR4", "PR5", "PR6", "PR7",
2016 Mar 14
2
[PATCH v1 01/19] mm: use put_page to free page instead of putback_lru_page
On 03/11/2016 08:30 AM, Minchan Kim wrote:
> Procedure of page migration is as follows:
>
> First of all, it should isolate a page from LRU and try to
> migrate the page. If it is successful, it releases the page
> for freeing. Otherwise, it should put the page back to LRU
> list.
>
> For LRU pages, we have used putback_lru_page for both freeing
> and putback to LRU
2016 Mar 14
2
[PATCH v1 01/19] mm: use put_page to free page instead of putback_lru_page
On 03/11/2016 08:30 AM, Minchan Kim wrote:
> Procedure of page migration is as follows:
>
> First of all, it should isolate a page from LRU and try to
> migrate the page. If it is successful, it releases the page
> for freeing. Otherwise, it should put the page back to LRU
> list.
>
> For LRU pages, we have used putback_lru_page for both freeing
> and putback to LRU
2007 Dec 11
1
R computing speed
Dear helpers,
I am using R version 2.5.1 to estimate a multinomial logit model using my
own maximum likelihood function (I work with share data and the default
function of R cannot deal with that).
However, the computer (I have an Athlon XP 3200+ with 512 GB ram) takes
quite a while to estimate the model.
With 3 categories, 5 explanatory variables and roughly 5000 observations it
takes 2-3 min.
2020 Jan 10
2
SUGGESTION: Settings to disable forked processing in R, e.g. parallel::mclapply()
If I understand the thread correctly this is an RStudio issue and I would suggest that the developers consider using pthread_atfork() so RStudio can handle forking as they deem fit (bail out with an error or make RStudio work). Note that in principle the functionality requested here can be easily implemented in a package so R doesn?t need to be modified.
Cheers,
Simon
Sent from my iPhone
2016 Apr 10
0
what is the faster way to search for a pattern in a few million entries data frame ?
On 04/10/2016 03:27 PM, Fabien Tarrade wrote:
> Hi Duncan,
>> Didn't you post the same question yesterday? Perhaps nobody answered
>> because your question is unanswerable.
> sorry, I got a email that my message was waiting for approval and when I
> look at the forum I didn't see my message and this is why I sent it
> again and this time I did check that the
2009 Feb 08
2
how to make this qq plot in lattice and/or ggplot2
Hi Group,
Here is some data.
p <- runif(1000) # sample data
groups <- rep(c(1,2),each=500) #conditioning variable
mydata <- cbind(p,groups)
n <- length(p)
u <- (1:n)/(n + 1) # uniform distribution reference for qqplot
logp <- -log(p,base=10)
logu <- -log(u,base=10)
qqplot(logp,logu)
How can I make the above qqplot in lattice and/or ggplot2. The sample
is uniform, and I take
2005 May 04
4
rank of a matrix
how do I check the rank of a matrix ?
say
A= 1 0 0
0 1 0
then rank(A)=2
what is this function?
thanks
I did try help.search("rank"), but all the returned help information
seem irrelevant to what I want.
I would like to know how people search for help information like this.
rank(base) Sample Ranks
SignRank(stats) Distribution of the
2020 Jan 11
1
SUGGESTION: Settings to disable forked processing in R, e.g. parallel::mclapply()
> On Jan 10, 2020, at 3:10 PM, G?bor Cs?rdi <csardi.gabor at gmail.com> wrote:
>
> On Fri, Jan 10, 2020 at 7:23 PM Simon Urbanek
> <simon.urbanek at r-project.org> wrote:
>>
>> Henrik,
>>
>> the example from the post works just fine in CRAN R for me - the post was about homebrew build so it's conceivably a bug in their libraries.
>
> I
2020 Jan 10
6
SUGGESTION: Settings to disable forked processing in R, e.g. parallel::mclapply()
Henrik,
the example from the post works just fine in CRAN R for me - the post was about homebrew build so it's conceivably a bug in their libraries. That's exactly why I was proposing a more general solution where you can simply define a function in user-space that will issue a warning or stop on fork, it doesn't have to be part of core R, there are other packages that use fork() as
2005 Feb 11
1
how ot get covariance matrix from survreg
I have a question, I generated some data and tried survreg to analyze
them, but here, I want to get the covariance matrix of the coefficients.
I know how to get corr from survreg, say, summary(f,corr=T), but how to
get covariance matrix of the coefficient ?
can I put them in a matrix and output ?
thanks
below is what I did
<mailto:r-help@stat.math.ethz.ch>
n=100; beta=1.0
2007 Aug 10
0
half-logit and glm (again)
I know this has been dealt with before on this list, but the previous
messages lacked detail, and I haven't figured it out yet.
The model is:
\x_{ij} = \mu + \alpha_i + \beta_j
\alpha is a random effect (subjects), and \beta is a fixed effect
(condition).
I have a link function:
p_{ij} = .5 + .5( 1 / (1 + exp{ -x_{ij} } ) )
Which is simply a logistic transformed to be between .5 and 1.
2012 Sep 14
1
parallel version of tapply() or table()?
Hello R-helpers.
I've tried to recreate a parallel version of tapply() and table() using a combination of the parallel functions mclapply() and pvec() and papply(), but haven't been successful. In the end, I'm trying to get a cross tab of two vectors. I currently (can) use tapply(..., sum) and table(), and even xtabs() and ftable(), but with tens of millions of words and tens of
2020 Jan 11
2
SUGGESTION: Settings to disable forked processing in R, e.g. parallel::mclapply()
Henrik,
the whole point and only purpose of mc* functions is to fork. That's what the multicore package was about, so if you don't want to fork, don't use mc* functions - they don't have any other purpose. I really fail to see the point - if you use mc* functions you're very explicitly asking for forking - so your argument is like saying that print() should have an option to
2012 Oct 26
0
parallel::pvec FUN types differ when v is a list; code simplifications?
In pvec(list(1, 2), FUN, mc.cores=2) FUN sees integer() arguments whereas
pvec(list(1, 2, 3), FUN, mc.cores=2) FUN sees list() arguments; the latter seems
consistent with pvec's description.
This came up in a complicated Bioconductor thread about generics and parallel
evaluation
https://stat.ethz.ch/pipermail/bioc-devel/2012-October/003745.html
One relevant point is that a
2011 Aug 26
1
matrix bands
Dear R developers,
I was looking for a function analogous to base::diag() for getting and
setting bands of a matrix. The closest I could find was Matrix::band(),
but this was not exactly what I wanted for two reasons. Firstly,
Matrix::band() returns a matrix rather than just the specified band.
Secondly, Matrix::band() cannot be used for setting the values for a
matrix band.
Setting or