search for: wichmann

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 Knuth-TAOCP-2002, M=2^30, since this modulus is used. D = 4...

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 t...

...; #return 11682 RNGkind(kind=3D"Super-Duper"); sum(duplicated(runif(1e7))); #return 11542 RNGkind(kind=3D"Mersenne-Twister"); sum(duplicated(runif(1e7))); #return 11656 #These indicated there were 2^32 distinct values, which agrees with the=20 help info. RNGkind(kind=3D"Wichmann-Hill"); sum(duplicated(runif(1e7))); #return 0 #So for this method, there should be more than 2^32 distinct values. You may not get the exact numbers, but they should be close. So how to=20 explain above problem? I need generate a large sample without any ties, it seems to me=20 "Wichm...

...return 32-bit integer values that are converted to doubles, so they take at most 2^32 distinct values and long runs will return duplicated values." But I find that the cycles are not the same as the 32-bit integer. My test indicated that the cycles for Knuth's methods were 2^30 while Wichmann-Hill's cycle was larger than 2^32! No numbers were duplicated in 10M numbers generated by runif using Wichmann-Hill. The other three methods had cycle length of 2^32. So, anybody can explain this? And any improvement to the implementation can be made to increase the cycle length like the W...

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 no...

...: > You might need to do a meta data cleanup before rejoining the DC: > https://support.microsoft.com/en-us/kb/216498 > > Regards > Davor Vusir > > -- Skickat fr?n mobilusken! -- > ------------------------------------------------------------------------ > Fr?n: Karl Heinz Wichmann <mailto:wichmann-karl at web.de> > Skickat: ?2015-?07-?02 20:16 > Till: samba at lists.samba.org <mailto:samba at lists.samba.org> > ?mne: [Samba] Rejoin dc to domain > > > Hallo > > > When rejoining a dc to the domain I get the following error message: > &...

...behavior, but it's documented in ?Random: "Do not rely on randomness of low-order bits from RNGs. Most of the supplied uniform generators return 32-bit integer values that are converted to doubles, so they take at most 2^32 distinct values and long runs will return duplicated values (Wichmann-Hill is the exception, and all give at least 30 varying bits.)" The "Wichman-Hill" bit is interesting: RNGkind("Wichmann-Hill") length(table(runif(1e6))) ## [1] 1000000 length(table(runif(1e6))) ## [1] 1000000 Mersenne-Twister has a much much larger periodicity than Wic...

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 > Not even this got error message sometimes > .Random.seed <- c(0, 1:2) > runif(1) [1] 0.03381877 > But somet...

On Sun, 2 Apr 2017 19:02:35 +0200 Karl Heinz Wichmann via samba <samba at lists.samba.org> wrote: > Hallo Marc > > I change the loglevel to 10 > > > database > "dlopen /usr/lib/x86_64-linux-gnu/samba/bind9/dlz_bind9_9.so -d 10"; > > and i get following errors: > > 02-Apr-2017 18:47:44.389 samba_...

...y good help and give advice. Sorry for that. Try do a meta data cleanup "the GUI way"; check DNS, System container, AD sites and services etc. And remove any remains of the old DC. Regards Davor -- Skickat fr?n mobilusken! -- ----- Ursprungligt meddelande ----- Fr?n: "Karl Heinz Wichmann" <karl-heinz.wichmann at online.de> Skickat: ?2015-?07-?06 10:09 Till: "Davor Vusir" <davortvusir at gmail.com>; "samba at lists.samba.org" <samba at lists.samba.org> ?mne: Re: SV: [Samba] Rejoin dc to domain Dear Davor We receive an error message at the...

...andom: >> >> "Do not rely on randomness of low-order bits from RNGs. Most of the >> supplied uniform generators return 32-bit integer values that are >> converted to doubles, so they take at most 2^32 distinct values and long >> runs will return duplicated values (Wichmann-Hill is the exception, and >> all give at least 30 varying bits.)" >> >> The "Wichman-Hill" bit is interesting: >> >> RNGkind("Wichmann-Hill") >> length(table(runif(1e6))) >> ## [1] 1000000 >> length(table(runif(1e6))) >&gt...

...values that are converted to doubles, so they take at most 2^32 > distinct values and long runs will return duplicated values." But I > find that the cycles are not the same as the 32-bit integer. > > My test indicated that the cycles for Knuth's methods were 2^30 while > Wichmann-Hill's cycle was larger than 2^32! No numbers were duplicated > in 10M numbers generated by runif using Wichmann-Hill. The other three > methods had cycle length of 2^32. > > So, anybody can explain this? And any improvement to the > implementation can be made to increase the...

...I find that the cycles are not > the same as the 32-bit integer. > This is no bug. Cycle length and the set of possible values are different concepts. And please don't cross-post. Duncan Murdoch > My test indicated that the cycles for Knuth's methods were 2^30 while > Wichmann-Hill's cycle was larger than 2^32! No numbers were duplicated in > 10M numbers generated by runif using Wichmann-Hill. The other three > methods had cycle length of 2^32. > > So, anybody can explain this? And any improvement to the > implementation can be made to increase the...

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 method besides that? 3. How to generate 100 random standard normal deviates using the Box-Muller method for standard normal random deviates and...

There seems to be a minor problem with reproducing numbers from rnorm with Box-Muller. The pattern suggests it might have something to do with the value that gets dropped when an odd number of numbers is requested. (Details below.) Also, could "user-supplied" be added as an option for normal.kind in RNGkind. I'm sure the Box-Muller in R is better than my own attempt, but I would

Hallo When rejoining a dc to the domain I get the following error message: [2015/07/02 11:51:44.089786, 0] ../source4/librpc/rpc/dcerpc_util.c:729(dcerpc_pipe_auth_recv) Failed to bind to uuid e3514235-4b06-11d1-ab04-00c04fc2dcd2 for

...;s documented in ?Random: > > "Do not rely on randomness of low-order bits from RNGs. Most of the > supplied uniform generators return 32-bit integer values that are > converted to doubles, so they take at most 2^32 distinct values and long > runs will return duplicated values (Wichmann-Hill is the exception, and > all give at least 30 varying bits.)" > > The "Wichman-Hill" bit is interesting: > > RNGkind("Wichmann-Hill") > length(table(runif(1e6))) > ## [1] 1000000 > length(table(runif(1e6))) > ## [1] 1000000 > > Mersen...

...server services = -dns # please set the interfaces and bind interfaces like this. interfaces = YOUR_IP 127.0.0.1 bind interfaces only = yes now reboot the server. Reboot the pc. And try again. Greetz, Louis > -----Oorspronkelijk bericht----- > Van: Karl Heinz Wichmann [mailto:wichmann-karl at web.de] > Verzonden: maandag 3 april 2017 17:32 > Aan: L.P.H. van Belle > Onderwerp: ,Re: [Samba] samba Digest, Vol 172, Issue 2 > > Hello Louis > > The right are ok. If i change to internal dns of samba, the record will > be greated. > > I...

On Sun, 2 Apr 2017 20:37:00 +0200 Karl Heinz Wichmann <wichmann-karl at web.de> wrote: > Hallo Rowland > > At the moment we use the internal samba dns. > > I have startet dcpromo and we get every second following message: > > [2017/04/02 20:26:29.712194, 2] > ../source4/rpc_server/drsuapi/getncchanges.c:1483(getncch...

...nd says that the default is Mersenne-Twister, and when I start R interactively, I get in fact > RNGkind() [1] "Mersenne-Twister" "Inversion" However, during the execution of "R CMD check" I get > > ### ** Examples > > > > RNGkind() > [1] "Wichmann-Hill" "Inversion" This creates discrepancies between the behaviour of code that uses pseudo random numbers during "check" and otherwise. > version _ platform i686-pc-linux-gnu arch i686 os linux-gnu system i686, linux-gnu status major 1 minor...