Displaying 20 results from an estimated 2000 matches similar to: "precision problems in testing with Intel compilers"
2004 Aug 19
3
More precision problems in testing with Intel compilers
The Intel compiled version also fails the below test:
> ###------------ Very big and very small
> umach <- unlist(.Machine)[paste("double.x", c("min","max"), sep='')]
> xmin <- umach[1]
> xmax <- umach[2]
> tx <- unique(outer(-1:1,c(.1,1e-3,1e-7)))# 7 values (out of 9)
> tx <- unique(sort(c(outer(umach,1+tx))))# 11 values
2004 Aug 20
1
make check failed with a minor error
Hi,
I am building R off the source file "The latest release (2004-06-21):
R-1.9.1.tgz <http://cran.stat.ucla.edu/src/base/R-1.9.1.tgz> " on RH
Linux 7.3. After the build the "make check" failed with an error which I
judge to be minor, but would like to hear from the experts in the field.
Is it harmeless? Can it indicate some problem with my computer setup
(not R)?
2004 Sep 06
1
qchisq (PR#7212)
Full_Name: David Clayton
Version: 1.8.1
OS: Linux
Submission from: (NULL) (131.111.126.242)
qchisq behaves very strangely when ncp is passed as zero (forcing internal
qnchisq to be called) when first argument is small.
Eg
> qchisq(1-1e-6, 1, ncp=0, lower.tail=TRUE)
qchisq(1-1e-6, 1, ncp=0, lower.tail=TRUE)
[1] 1024
while, if ncp is unspecified,
> qchisq(1-1e-6, 1)
qchisq(1-1e-6, 1)
2004 Jan 19
2
small bug on qchisq (PR#6442)
Full_Name: Drouilhet R?my
Version: 1.8.1
OS: Linux
Submission from: (NULL) (195.221.43.136)
qchisq(1,10) works well but qchisq(1,10,ncp=0) does not work whereas ncp=0 is
the default value of the function qchisq(1,10). (of course, 10 will be replaced
by any integer value).
Let us notice that this bug occurs only when applying probability one.
(qchisq(seq(0,.9,.1),10,ncp=0) works very well).
2003 Apr 13
2
Peculiarity in non-central qchisq for ncp > 294.92 ...
Hello all,
Here's my query:
Running R 1.6.2 on FreeBSD 5.0, and on WinXP, and I find that the
following hangs the process:
dchisq(alpha=0.01, df=1, ncp=295)
but it does work for ncp < 294.92.
Is this general?
Best wishes to all,
Andrew
Andrew Robinson Ph: 208 885 7115
Department of Forest Resources Fa: 208 885 6226
University of Idaho E : andrewr at uidaho.edu
PO
2008 Jan 07
2
chi-squared with zero df (PR#10551)
Full_Name: Jerry W. Lewis
Version: 2.6.1
OS: Windows XP Professional
Submission from: (NULL) (24.147.191.250)
pchisq(0,0,ncp=lambda) returns 0 instead of exp(-lambda/2)
pchisq(x,0,ncp=lambda) returns NaN instead of exp(-lambda/2)*(1 +
SUM_{r=0}^infty ((lambda/2)^r / r!) pchisq(x, df + 2r))
qchisq(.7,0,ncp=1) returns 1.712252 instead of 0.701297103
qchisq(exp(-1/2),0,ncp=1) returns 1.238938
2001 Dec 09
1
Help for Power analysis
Dear colleague,
I not sure this R code is correctly ? I would to show
the number of Sample Size at Sample Size Axis that line
draw from Power Axis (80%) from R code.
How I show this and select the most appropriate of
this power (.79955687 - 80983575).
Thank for your help and answer.
Best Regards,
Nikom Thanomsieng,
Email: nikom at kku.ac.th
....
#Power analysis: Sample size for
2001 Mar 10
1
Bug in qchisq?
Hello developers and users:
My system fails (the computer freezes) when I use the ncp parameter,
with the lower.tail=FALSE option in the qchisq function.
qchisq(0.025,31,ncp=1,lower.tail=FALSE)
Thank you very much for your help.
Kenneth Cabrera
Universidad Nacional de Colombia
ICNE
Sede Medellin
krcabrer at perseus.unalmed.edu.co
PS
I am using:
$platform "i386-pc-mingw32"
2001 Mar 10
0
Re: [R] Bug in qchisq? (PR#875)
Kenneth Cabrera <krcabrer@epm.net.co> writes:
> Hello developers and users:
>
> My system fails (the computer freezes) when I use the ncp parameter,
> with the lower.tail=FALSE option in the qchisq function.
>
> qchisq(0.025,31,ncp=1,lower.tail=FALSE)
Yup, that's a bug. We have in pnchisq.c
48 for (ux = 1.0; pnchisq(ux, n, lambda, lower_tail, log_p) <
2001 Mar 13
0
Re: [R] Bug in qchisq? (PR#875)
>>>>> "PD" == p dalgaard <p.dalgaard@biostat.ku.dk> writes:
PD> Kenneth Cabrera <krcabrer@epm.net.co> writes:
>> Hello developers and users:
>>
>> My system fails (the computer freezes) when I use the ncp parameter,
>> with the lower.tail=FALSE option in the qchisq function.
>>
>>
2003 Mar 08
2
Looking for non-central F quantile
Greetings all,
I'm trying to figure out how to calculate the inverse CDF (i.e. a
quantile) for a non-central F distribution. I could put together a quick
numerical solver routine using the CDF, but I wonder if there's a function
that I've missed that would be more efficient?
Thank-you,
Andrew
Andrew Robinson Ph: 208 885 7115
Department of Forest Resources Fa: 208 885
2009 Oct 11
2
Accuracy (PR#13999)
Full_Name: Viktor Witkovsky
Version: 2.9.2
OS: Windows XP
Submission from: (NULL) (78.98.89.227)
Hello,
I have found strange behavior of the function qchisq (the non-central qchisq is
based on inversion of pchisq, which is further based on pgamma). The function
gives wrong results without any warning. For example:
qchisq(1e-12,1,8.94^2,lower.tail=FALSE) gives 255.1840972465858 (notice that
2005 Jun 15
1
Chi square convolution?
Hi,
I want to determine the confidence interval on the sum of two sigma's.
Is there an easy way to do this in R? I guess I have to use some sort of
chisquare convolution algorithm???
Thanx,
Roy
--
The information contained in this communication and any atta...{{dropped}}
2003 Feb 14
1
FW: [Fwd: Re: [S] Exact p-values]
Dear all
Just for fun, I have just downloaded the paper mentioned below and checked
it with R-1.6.1.
Everything is ok with exception of Table 2b, where I get always 1 instead of
0.5:
> pbinom(1e15,2e15,0.5)
[1] 1
Which value should be correct?
Best regards
Christian Stratowa
==============================================
Christian Stratowa, PhD
Boehringer Ingelheim Austria
Dept NCE Lead
2009 Dec 14
0
R 2.10.1 is released
R-2.10.1.tar.gz was built a short while ago.
This is a maintenance release and fixes a number of mostly minor issues.
See the full list of changes below.
You can get it from
http://cran.r-project.org/src/base/R-2/R-2.10.1.tar.gz
or wait for it to be mirrored at a CRAN site nearer to you. Binaries
for various platforms will appear in due course.
For the R Core Team
Peter
2009 Dec 14
0
R 2.10.1 is released
R-2.10.1.tar.gz was built a short while ago.
This is a maintenance release and fixes a number of mostly minor issues.
See the full list of changes below.
You can get it from
http://cran.r-project.org/src/base/R-2/R-2.10.1.tar.gz
or wait for it to be mirrored at a CRAN site nearer to you. Binaries
for various platforms will appear in due course.
For the R Core Team
Peter
2008 Feb 07
3
how to calculate chisq value in R
for example, an expression such as chisq(df=1,ncp=0) ?
thanks
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View this message in context: http://www.nabble.com/how-to-calculate-chisq-value-in-R-tp15338943p15338943.html
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2002 Oct 17
3
Non-central distributions
Hi Folks,
I note that, while the "chisq" functions
dchisq(x, df, ncp=0, log = FALSE)
pchisq(q, df, ncp=0, lower.tail = TRUE, log.p = FALSE)
qchisq(p, df, ncp=0, lower.tail = TRUE, log.p = FALSE)
rchisq(n, df, ncp=0)
all have a slot for the non-centrality parameter "ncp", of
the functions for the t and F distributions:
dt(x, df, log = FALSE)
2006 Jan 17
1
how can i locate the source code of a module quickly?
I have dowloaded the Source Code of R,and I want to know the process of
chi-sqared test,but how can I found it?
[[alternative HTML version deleted]]
2006 Mar 08
1
power and sample size for a GLM with Poisson response variable
Craig, Thanks for your follow-up note on using the asypow package. My
problem was not only constructing the "constraints" vector but, for my
particular situation (Poisson regression, two groups, sample sizes of
(1081,3180), I get very different results using asypow package compared
to my other (home grown) approaches.
library(asypow)
pois.mean<-c(0.0065,0.0003)
info.pois <-