Displaying 20 results from an estimated 1000 matches similar to: "Problems with setting .Random.seed (PR#179)"
2008 Aug 17
1
Wichmann-Hill Random Number Generator and the Birthday Problem
Dear all,
Recently I am generating large random samples (10M) and any duplicated
numbers are not desired.
We tried several RNGs in R and found Wichmann-Hill did not produce
duplications.
The duplication problem is the interesting birthday problem. If there are
M possible numbers, randomly draw N numbers from them,
the average number of dupilcations D = N(N-1)/2/M.
For Knuth-TAOCP and
1999 Apr 28
1
R random number generator
R 0.64 on windows NT 4.0
Sometimes I got an error message by doing this
> .Random.seed <- c(1, 1:2)
> .Random.seed
[1] 1 1 2
> runif(5)
Warning: Wrong length .Random.seed; forgot initial RNGkind? set to Wichmann-Hill[1] 0.02253721 0.84832584 ........
Sometimes I do not get error message:
> .Random.seed <- c(1, 1:2)
> .Random.seed
[1] 1 1 2
> runif(1)
[1] 0.5641106
>
2005 Nov 17
2
R questions
Dear Sir/Madam,
I am a beginner in R. Here is my questions.
1. Can you give me one test for randomness (a name and descriptive
paragraph is sufficient).
2. I have learned a uniform random number generator [e.g. not the
algorithms: i)Wichmann-Hill, ii) Marsaglia-Multicarry, iii) Super-Duper
(Marsaglia), iv) Mersenne-Twister, v) TAOCP-1997 (Knuth), or vi) TAOCP-2002
(Knuth)] . Is there any other
2008 Aug 14
2
[R] RNG Cycle and Duplication (PR#12540)
This message is in MIME format. The first part should be readable text,
while the remaining parts are likely unreadable without MIME-aware tools.
---559023410-851401618-1218751024=:15885
Content-Type: TEXT/PLAIN; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: QUOTED-PRINTABLE
I didn't describe the problem clearly. It's about the number of distinct=20
values. So just
1999 Jun 12
0
Random numbers
Hi,
I have a few questions about the RNG in R; apologies if these are dumb
questions:
1. It is my understanding that, among the three types of random number
generators available in R now, the best one is the Marsaglia Multicarry. Is
this correct?
2. How does the best RNG in R compare (in terms of quality) to the RNG in
SPlus? (based on Marsaglia's Super Duper)? Does the Super-Duper in
1999 May 05
1
RNG R/Splus compatibility
Starting with example Wichmann-Hill code from Brian Ripley I have been playing
with a set of programs for getting the same random sequences from R and Splus. A
copy is included below along with a test (which works in Solaris with R and
Splus 3.3).
The approach is somewhat different from the usual problems on this list as I am
trying to get the same results from Splus as I get from R. However,
1997 Sep 15
0
R-alpha: set.seed(.) [was 'compatibility']
>>>>> Thomas Lumley writes:
>> Two compatibility issues found while trying to convert a simulation
>> from S to R.
>> 1. set.seed() We don't have this function. According to Venables &
>> Ripley it just picks a seed from a list of 1000 possibilities. How about
>>
>> "set.seed" <-function (i)
2003 Oct 16
2
.Random.seed
I am writing a function for the purposes of a simulation. Due to memory
problems, the function sometimes crashes. In order to get around this
problem, I would like to include to be able to save the "last" seed, so I
can pick up with the next run of the simulation after a "crash". I am
having trouble understanding what is going on with .Random.seed!
For each run of the
2008 Aug 19
1
RNGkind() state (PR#12567)
I sent this to R-devel early last month, but have received no response, so I guess it
really is a bug.
This looks like a bug to me, and is a bit hard to describe, but easy to reproduce. ?
Basically, if RNGkind is saved as something other than the default, and if the first
operation in a session is a set.seed(), the default is reverted to. ?Reproduce by:
cafe-rozo> ?R --vanilla
R version
2008 Jul 07
0
RNGkind() state
This looks like a bug to me, and is a bit hard to describe, but easy to reproduce.
Basically, if RNGkind is saved as something other than the default, and if the first
operation in a session is a set.seed(), the default is reverted to. Reproduce by:
cafe-rozo> R --vanilla
R version 2.7.1 (2008-06-23)
Copyright (C) 2008 The R Foundation for Statistical Computing
ISBN 3-900051-07-0
R is
2002 Aug 12
1
set.seed
I'm running into problems with set.seed--maybe I'm misunderstanding
something.
I'm running R 1.5.1 on Windows 2000.
I'm basically trying to capture the random seed so that I can reproduce a
simulation if it's necessary later. Using set.seed, I can certainly get
reproducible results, but not the results I get on the first pass. Here's
an example:
# Generate a random
2003 Jun 13
0
Testing the R RNGs
I have applied L'Ecuyer's TESTU01 suite of RNG tests
to the RNGs in R. TESTU01 offers three increasingly
more stringent suites, called "Small Crush", "Crush" and
"Big Crush". If a particular RNG fails Small Crush, there
is no need to apply Big Crush.
Below I summarize the results:
Number of Tests Failed
Small Crush Crush Big Crush
2023 Feb 16
0
User-defined RNG with the standalone Rmath library
I have two questions about using a user-defined random number generator (RNG) with the standalone Rmath library. The default RNG with the standalone Rmath library is the Marsaglia-multicarry generator, which has poor properties. The "R Installation and Administration" manual, in the section "The standalone Rmath library", states that:
```
A little care is needed to use the
2013 Oct 10
1
Replacing the Random Number Generator in Stand Alone Library
Hi R-Developers,
I had a question about the random number generator used in the R StandAlone
Math Library. The stand-alone library depends on the unif_rand() function
for most simulated values, and this function is provided in the sunif.c file
in the relevant directory. At present, this program implements the
"Marsaglia-Multicarry" algorithm, which is described throughout the R
1999 May 04
1
rnorm
Brian
I've been playing a bit with the Wichmann-Hill RNG. I would prefer to have
normally distributed random numbers and I think I have things generally worked
out to use Wichmann-Hill and then Box-Muller. In the process, I was looking at
R's rnorm.c, but could not figure out what transformation is used in R to
convert uniform rv's to normal rv's. Do you know? It looks like there
1998 Dec 01
0
Random Number Generators, .Random.seed and all that..
As some of you know,
we have been thinking of allowing the possibility of a
CHOICE of the kind of random number generator (=: RNG) to use in R.
The current R-release snapshot even has some code in it;
however, this will be changed quite a bit. Here is a kind of informal
RFC (request for comments / request for criticism / ..):
1a. With the new scheme, we still want that
save(..) &
2012 Jan 27
2
The following code (using rgamma) hangs
Hi,
I'm seeing something that may be a bug in R's standalone math library,
which is packaged by Debian as r-mathlib. I reported it to the Debian BTS
as http://bugs.debian.org/657573
I'm using Debian squeeze, and the code was tested with r-mathlib 2.11.1-6
(default on stable) and 2.14.1-1 (from testing/unstable).
I summarize this report below. The following code with the R math
2000 Dec 14
0
using R's random numbers in another program
Dear All,
I want to use R's random number in a C++ program (I can link libRmath either
as shared or static library). I have two questions:
1. If I understand correctly, the underlaying random number generator will be
Marsaglia-multicarry, UNLESS I provide my own. In other words (unless I
provide it) I cannot use some of the other RNG's available from within R, such
as Mersenne-Twister?
2001 Oct 18
0
uniform generator (default)
Recieving digests.
> RNGkind(NULL)
[1] "Marsaglia-Multicarry" "Kinderman-Ramage"
I would appreciate it if anybody has any comments on the following.
Please do not comment on the R functions themselves, since they merely
mimic a (bivariate simplification of a) C routine called from S.
In particular, I would like to know if anything is available with regard
to the
1998 Nov 09
0
S-Plus RNG (fwd)
Forwarded message:
>From BMCCULLO at fcc.gov Fri Nov 6 12:50:07 1998
Message-Id: <s642efa3.006 at fcc.gov>
X-Mailer: Novell GroupWise 4.1
Date: Fri, 06 Nov 1998 12:51:24 -0500
From: Bruce McCullough <BMCCULLO at fcc.gov>
To: mai at ms.uky.edu
Subject: S-Plus RNG
Mime-Version: 1.0
Content-Type: text/plain
Content-Disposition: inline
Mai,
Someone forwarded to me your e-mail about