Displaying 20 results from an estimated 800 matches similar to: "Modifying Internal C Files"
2008 Apr 25
0
remarks on function pnbeta
Dear Developers,
The pnbeta function has been reviewed recently in the article of A.
Baharev, S. Kem?ny, On the computation of the noncentral F and
noncentral beta distribution, Statistics and Computing, 2008, in
press. Preprint of the paper is available here:
http://reliablecomputing.eu/publications.html
and the article here
http://dx.doi.org/10.1007/s11222-008-9061-3
I suggest increasing
2008 Apr 25
0
remarks on function pnbeta (PR#11277)
Dear Developers,
The pnbeta function has been reviewed recently in the article of A.
Baharev, S. Kem=E9ny, On the computation of the noncentral F and
noncentral beta distribution, Statistics and Computing, 2008, in
press. Preprint of the paper is available here:
http://reliablecomputing.eu/publications.html
and the article here
http://dx.doi.org/10.1007/s11222-008-9061-3
I suggest increasing
2008 Aug 21
1
pnmath compilation failure; dylib issue?
(1) ...need to speed up a monte-carlo sampling...any suggestions about
how I can get R to use all 8 cores of a mac pro would be most useful
and very appreciated...
(2) spent the last few hours trying to get pnmath to compile under os-
x 10.5.4...
using gcc version 4.2.1 (Apple Inc. build 5553) as downloaded from
CRAN, xcode 3.0...
...xcode 3.1 installed over top of above after
2009 Mar 17
3
R does not compile any more on FreeBSD 8.0-CURRENT
On a recent FreeBSD 8.0-CURRENT (i386) building R (any version) breaks
with the following messages:
----------------------------------------------------------------------
[...snip...]
gcc -std=gnu99 -I. -I../../src/include -I../../src/include
-I/usr/local/include -DHAVE_CONFIG_H -g -O2 -c wilcox.c -o wilcox.o
gcc -std=gnu99 -I. -I../../src/include -I../../src/include
-I/usr/local/include
2020 Mar 26
4
unstable corner of parameter space for qbeta?
I've discovered an infelicity (I guess) in qbeta(): it's not a bug,
since there's a clear warning about lack of convergence of the numerical
algorithm ("full precision may not have been achieved"). I can work
around this, but I'm curious why it happens and whether there's a better
workaround -- it doesn't seem to be in a particularly extreme corner of
parameter
2012 May 15
1
R-devel on FreeBSD: new C99 functions don't build
About April 25th, there had been some changes within R-devel's
src/nmath/pnbeta.c (and probably some other relevant places) and now
building R-devel on FreeBSD 10.0-CURRENT (amd64) with gcc-4.6.4 and
math/R-devel (selfmade forked port from math/R) fails like this:
[..snip..]
mkdir /usr/ports/math/R-devel/work/R-devel/bin/exec
gcc46 -std=gnu99 -I../../src/extra -I. -I../../src/include
2020 Mar 26
2
unstable corner of parameter space for qbeta?
Given that a number of us are housebound, it might be a good time to try to
improve the approximation. It's not an area where I have much expertise, but in
looking at the qbeta.c code I see a lot of root-finding, where I do have some
background. However, I'm very reluctant to work alone on this, and will ask
interested others to email off-list. If there are others, I'll report back.
2005 Oct 24
1
Problems with pf() with certain noncentral values/degrees of freedom combinations
Hello all.
It seems that the pf() function when used with noncentral parameters can
behave badly at times. I've included some examples below, but what is
happening is that with some combinations of df and ncp parameters,
regardless of how large the quantile gets, the same probability value is
returned. Upon first glance noncentral values greater than 200 may seem
large, but they are in
2000 Nov 28
1
non-centrality parameter in pf() (PR#752)
Bug Description:
Problem with the function pf() when the non-centrality
parameter is large. Here is a sample command. You should
see a smooth line from 0 to about 55, and then the values
of pf() go crazy from 55 to 100.
############################
ncp <- seq(0,100,length=200)
plot(ncp,pf(5,7,2,ncp=ncp))
############################
Version:
platform = i686-pc-linux-gnu
arch = i686
os =
2010 Jul 15
1
Warning message in summary of PGLM
Dear Sir,
When requesting the summary of pglm analyses in R, I encounter repeatedly
the following warning message:
"Warning message:
In pf(Fstat, object$k - 1, object$n - object$k, ncp = 0, lower.tail = FALSE,
:
full precision was not achieved in 'pnbeta'"
This message appears both with the pglm estimate of Lambda and with Lambda
set to 0.
Could you tell me what
2000 Dec 14
2
Accuracy problem in dchisq for non-central chi-squared
Hi,
I think I have identified a inaccuracy in dchisq when the non-centrality
parameter is non-zero and large. Here's a little test:
sys.dchisq.test <- function(N = 100000,mean = 0)
{
z <- rnorm(N,mean = mean, sd = 1)
x <- z^2
xmin <- min(x)
xmax <- max(x)
br <- seq(xmin,xmax,length = 101)
dbr <- br[2]-br[1]
hist(x,br)
p <- dchisq(br,df = 1,ncp =
2020 Mar 26
2
unstable corner of parameter space for qbeta?
Despite the need to focus on pbeta, I'm still willing to put in some effort.
But I find it really helps to have 2-3 others involved, since the questions back
and forth keep matters moving forward. Volunteers?
Thanks to Martin for detailed comments.
JN
On 2020-03-26 10:34 a.m., Martin Maechler wrote:
>>>>>> J C Nash
>>>>>> on Thu, 26 Mar 2020
2003 May 01
2
qbeta hang (PR#2894)
Full_Name: Morten Welinder
Version: 1.6.1
OS: Solaris/sparc
Submission from: (NULL) (65.213.85.144)
qbeta(0.1, 1e-8, 0.5, TRUE, FALSE) seems to hang for me.
2013 May 14
2
invalid operands of types ‘SEXPREC*’ and ‘R_len_t’ to binary ‘operator/’ with Rcpp.
Dear R-Developers,
I just started learning how to use Rcpp. Earlier while using it, I
encountered an error as shown below:
file74d8254b96d4.cpp: In function ‘Rcpp::NumericVector
foo(Rcpp::NumericVector, Rcpp::NumericVector, Rcpp::NumericVector,
Rcpp::Function, Rcpp::Function)’:
file74d8254b96d4.cpp:10: error: invalid operands of types ‘SEXPREC*’ and
‘R_len_t’ to binary ‘operator/’
make: ***
2005 Oct 11
2
Sometimes having problems finding a minimum using optim(), optimize(), and nlm() (while searching for noncentral F parameters)
Hi everyone.
I have a problem that I have been unable to determine either the best
way to proceed and why the methods I'm trying to use sometimes fail. I'm
using the pf() function in an optimization function to find a
noncentrality parameter that leads to a specific value at a specified
quantile. My goal is to have a general function that returns the
noncentrality parameter that
2007 Nov 24
2
how to compute highest density interval?
Suppose i want to compute a 95% highest density for a beta distribution
beta(a,b)
the two end points x1 and x2 shoudl satisfy the following two equations:
pbeta(x1,a,b)-pbeta(x2,a,b)=95%
dbeta(x1,a,b)=dbeta(x2,a,b)
Is there any fast way to compute x1 and x2 in R?
[[alternative HTML version deleted]]
2005 Feb 23
1
Re: [R-SIG-Mac] Bug running pbinom() in R-GUI?
The real problem is that pbeta can take forever. That's bug #7153 and a fix is
within reach.
Morten
2007 Oct 11
1
[Fwd: Re: pt inaccurate when x is close to 0 (PR#9945)]
Here's a contribution from Ian Smith that got bounced from the list.
-------- Original Message --------
Subject: Re: [Rd] pt inaccurate when x is close to 0 (PR#9945)
Date: Thu, 11 Oct 2007 06:02:43 -0400
From: iandjmsmith at aol.com
To: murdoch at stats.uwo.ca
Duncan,
I tried sending the rest of this to R-devel but it was rejected as spam,
hence the personal e-mail.
R calculates the pt
2005 Feb 11
1
Re: [R-SIG-Mac] Bug running pbinom() in R-GUI?
On Feb 10, 2005, at 7:38 PM, George W. Gilchrist wrote:
> Today I was running a graduate level stats lab using R and we
> encountered a
> major problem while using the current build of the Cocoa GUI:
>
>> From the GUI:
>> system.time(pbinom(80, 1e5, 806/1e6))
> [1] 14.37 4.94 30.29 0.00 0.00
>>
>
>> From the command line on the same machine:
>>
2002 Sep 22
3
binom.test()
Hello everybody.
Does anyone else find the last test in the following sequence odd?
Can anyone else reproduce it or is it just me?
> binom.test(100,200,0.13)$p.value
[1] 2.357325e-36
> binom.test(100,200,0.013)$p.value
[1] 6.146546e-131
> binom.test(100,200,0.0013)$p.value
[1] 1.973702e-230
> binom.test(100,200,0.00013)$p.value
[1] 0.9743334
(R 1.5.1, Linux RedHat 7.1)
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