similar to: pweibull.c (PR#1334)

Displaying 20 results from an estimated 900 matches similar to: "pweibull.c (PR#1334)"

2002 Feb 28
4
pexp.c (PR#1335)
Full_Name: M Welinder Version: 1.4 OS: (src) Submission from: (NULL) (192.5.35.38) It seems to me that pexp can be improved in the lower_tail=TRUE and log_p=FALSE case by using expm1. Something like -expm1 (-x / scale); I think. -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send
2005 May 27
1
qcauchy accuracy (PR#7902)
Full_Name: Morten Welinder Version: 2.1.0 OS: src only Submission from: (NULL) (216.223.241.212) Now that pcauchy has been fixed, it is becoming clear that qcauchy suffers from the same problems. qcauchy(pcauchy(1e100,0,1,FALSE,TRUE),0,1,FALSE,TRUE) should yield 1e100 back, but I get 1.633178e+16. The code below does much better. Notes: 1. p need not be finite. -Inf is ok in the log_p
2004 Oct 22
3
pgamma discontinuity (PR#7307)
Full_Name: Morten Welinder Version: 2 OS: Solaris/space/gcc2.95.2 Submission from: (NULL) (65.213.85.217) I changed src/nmath/standalone/test.c to read: --------------------------------------------------------------------------------- #define MATHLIB_STANDALONE 1 #include <Rmath.h> #include <stdio.h> int main() { double x; for (x = 99990; x <= 100009; x++) printf
2004 Apr 19
2
pgeom accuracy (PR#6792)
Full_Name: Morten Welinder Version: snapshot OS: Submission from: (NULL) (65.213.85.218) This should fix the remaining two 1-p cancellation issues. double l_rt = log1p (-p) * (x + 1); if (log_p) return R_DT_Clog (l_rt); else return lower_tail ? -expm1 (l_rt) : exp (l_rt);
2004 Mar 24
1
R_DT_val accuracy (PR#6692)
Full_Name: M. Welinder Version: 1.8.1 OS: Solaris Submission from: (NULL) (65.213.85.227) Currently R has... #define R_D_Lval(p) (lower_tail ? (p) : (1 - (p))) /* p */ #define R_D_val(x) (log_p ? log(x) : (x)) /* x in pF(x,..) */ #define R_DT_val(x) R_D_val(R_D_Lval(x)) /* x in pF */ ...which is sub-optimal in the lower_tail==FALSE && log_p==TRUE case. Something like this ought
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
2004 Apr 11
3
pcauchy precision (PR#6756)
Full_Name: Morten Welinder Version: snapshot OS: Submission from: (NULL) (65.213.85.129) Two things are wrong. 1. There is nan test outside IEEE_754. 2. The meat part of the function should really be something like... if (!lower_tail) x = -x; if (fabs (x) > 1) { double temp = atan (1 / x) / M_PI; return (x > 0) ? R_D_Clog (temp) : R_D_val (-temp); } else
2004 Apr 15
0
phyper accuracy and efficiency (PR#6772)
Full_Name: Morten Welinder Version: snapshot OS: Submission from: (NULL) (65.213.85.218) Time to kick phyper's tires... The current version has very serious cancellation issues. For example, if you ask for a small right-tail you are likely to get total cancellation. For example phyper(59, 150, 150, 60, FALSE, FALSE) gives 6.372680161e-14. The right answer is dhyper(0, 150, 150, 60,
2020 Aug 10
2
qnbinom with small size is slow
Thanks Ben for verifying the issue. It is always reassuring to hear when others can reproduce the problem. I wrote a small patch that fixes the issue (https://github.com/r-devel/r-svn/pull/11): diff --git a/src/nmath/qnbinom.c b/src/nmath/qnbinom.c index b313ce56b2..d2e8d98759 100644 --- a/src/nmath/qnbinom.c +++ b/src/nmath/qnbinom.c @@ -104,6 +104,7 @@ double qnbinom(double p, double size,
2002 Oct 25
0
qgamma precision (PR#2214)
Full_Name: Morten Welinder Version: 1.5.1 OS: Solaris Submission from: (NULL) (65.213.85.136) I was having problems with qgamma's precision in the sense that pgamma(qpgamma(x)) was not as close to the identity function as I would like. I was seeing relative errors with random input of about 1e-8. This fits nicely with the code'd EPS2 value of 5e-7. To solve this I added a newton step
2002 Jul 25
4
src/nmath/pgeom.c (PR#1834)
Full_Name: Morten Welinder Version: 1.5.1 OS: Solaris/Linux Submission from: (NULL) (192.5.35.38) The line return log(1 - p) * (x + 1); looks like it has problems for p near 1. I would suggest rewriting it to return log1p (-p) * (x + 1); -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-devel mailing list -- Read
2002 May 12
2
Is this a bug of pweibull()? (Follow up)
Please allow me to add just a little more about this: nothing wrong with pweibull(), namely, the two cases I reported: pweibull(3:10, 2) and pweibull(3:10, 2.1), in rw1041 and earlier version. I wonder this might just due to the change from rw1041 to rw1050, however, I can't find anything relevant (seems to me) in the News or Readme. Thanks Sundar for the suggestion of using 1 -
2002 May 11
4
Is this a bug of pweibull()?
In rw1050, I found that > pweibull(3:10, 2) [1] 0.9998766 0.9999999 1.0000000 1.0000000 NaN NaN [7] NaN NaN Warning message: NaNs produced in: pweibull(q, shape, scale, lower.tail, log.p) more surprisingly, > pweibull(3:10, 2.1) [1] 0.9999566 1.0000000 1.0000000 -Inf NaN NaN [7] NaN NaN Warning message: NaNs produced in: pweibull(q,
2005 Aug 09
0
qpois minor bug (PR#8058)
Full_Name: Mikael Weigelt Version: 2.0 OS: windows Submission from: (NULL) (207.171.180.101) The calculation of the qpois attempts to use the Cornish-Fisher expansion as a starting approximation. The definition of the expansion is incorrect. However, since this approximation just gives an initial solution, the end result of the function is still correct. To fix the approximation, in the
2020 Aug 20
0
qnbinom with small size is slow
>>>>> Constantin Ahlmann-Eltze via R-devel >>>>> on Mon, 10 Aug 2020 10:05:36 +0200 writes: > Thanks Ben for verifying the issue. It is always reassuring to hear > when others can reproduce the problem. > I wrote a small patch that fixes the issue > (https://github.com/r-devel/r-svn/pull/11): > diff --git
2004 Jan 15
1
Exactness of ppois
Hello, by checking the precision of a convolution algorithm, we found the following "inexactness": We work with R Version 1.8.1 (2003-11-21) on Windows systems (NT, 2000, XP). Try the code: ## Kolmogorov distance between two methods to ## determine P(Poisson(lambda)<=x) Kolm.dist <- function(lam, eps){ x <- seq(0,qpois(1-eps, lambda=lam), by=1) max(abs(ppois(x,
2020 Aug 21
1
qnbinom with small size is slow
Hi Martin, thanks for verifying. I agree that the Cornish-Fisher seems to struggle with the small size parameters, but I also don't have a good idea how to replace it. But I think fixing do_search() is possible: I think the problem is that when searching to the left y is decremented only if `pnbinom(y - incr, n, pr, /*l._t.*/TRUE, /*log_p*/FALSE)) < p` is FALSE. I think the solution is
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. >> >>
2020 Aug 07
2
qnbinom with small size is slow
Hi all, I recently noticed that `qnbinom()` can take a long time to calculate a result if the `size` argument is very small. For example qnbinom(0.5, mu = 3, size = 1e-10) takes ~30 seconds on my computer. I used gdb to step through the qnbinom.c implementation and noticed that in line 106 (https://github.com/wch/r-source/blob/f8d4d7d48051860cc695b99db9be9cf439aee743/src/nmath/qnbinom.c#L106)