similar to: Wish List: Extensions to the derivatives table

The issue is that without an extensible derivative table or the proposed extensions, it is not possible to automatically produce (without manual modification of the deriv3 output) a function that avoids catastrophic cancellation regardless of the working range. Manual modification is not onerous as a one-time exercise, but can be time consuming when it must be done numerous times, for example

The same argument would hold for tan(pi/2). I don't say the result 'NaN' is wrong, but I thought, tan(pi*x) and tanpi(x) should give the same result. Hans Werner On Fri, Sep 9, 2016 at 8:44 PM, William Dunlap <wdunlap at tibco.com> wrote: > It should be the case that tan(pi*x) != tanpi(x) in many cases - that is why > it was added. The limits from below and below of the

hi, my environment... > sessionInfo() R version 3.3.2 (2016-10-31) Platform: x86_64-pc-linux-gnu (64-bit) Running under: Debian GNU/Linux 8 (jessie) locale: [1] LC_CTYPE=ja_JP.UTF-8 LC_NUMERIC=C [3] LC_TIME=ja_JP.UTF-8 LC_COLLATE=ja_JP.UTF-8 [5] LC_MONETARY=ja_JP.UTF-8 LC_MESSAGES=ja_JP.UTF-8 [7] LC_PAPER=ja_JP.UTF-8 LC_NAME=C [9] LC_ADDRESS=C

As the subject line says, we get different results for tan(pi/2) and tanpi(1/2), though this should not be the case: > tan(pi/2) [1] 1.633124e+16 > tanpi(1/2) [1] NaN Warning message: In tanpi(1/2) : NaNs produced By redefining tanpi with sinpi and cospi, we can get closer: > tanpi <- function(x) sinpi(x) / cospi(x) > tanpi(c(0, 1/2, 1, 3/2, 2))

Hi. Unless I'm misremembering, log, exp, sin, cos, and tan are all handled in deriv3. The functions listed are specially coded slightly more accurate versions but can be substituted with native ones for which deriv/deriv3 will work automatically. I believe that if you write your functions using log(a + 1) instead of log1p(a) or log(x) / log(2) instead of log2(x) deriv3 will work fine.

>>>>> Martin Maechler <maechler at stat.math.ethz.ch> >>>>> on Thu, 1 Dec 2016 09:36:10 +0100 writes: >>>>> Ei-ji Nakama <nakama at ki.rim.or.jp> >>>>> on Thu, 1 Dec 2016 14:39:55 +0900 writes: >> Hi, >> i try sin, cos, and tan. >>> sapply(c(cos,sin,tan),function(x,y)x(y),1.23e45*pi)

Hi, i try sin, cos, and tan. > sapply(c(cos,sin,tan),function(x,y)x(y),1.23e45*pi) [1] 0.5444181 0.8388140 1.5407532 However, *pi results the following > sapply(c(cospi,sinpi,tanpi),function(x,y)x(y),1.23e45) [1] 1 0 0 Please try whether the following becomes all right. diff -ruN R-3.3.2.orig/src/nmath/cospi.c R-3.3.2/src/nmath/cospi.c --- R-3.3.2.orig/src/nmath/cospi.c 2016-09-15

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

Hello, I am trying to use Yan and Rossini's Makefile for cross building Windows versions of R packages in Linux with R 1.9.0. When compiling R with the mingw tools I get an error about expm1 being undeclared when first found at src/main/arithmetic.c:1019 If I fiddle a bit with it later on I also get errors about log1p bein undeclared. Any idea what should I look for? I am using R 1.9.0 in

Hello, I am trying to use Yan and Rossini's Makefile for cross building Windows versions of R packages in Linux with R 1.9.0. When compiling R with the mingw tools I get an error about expm1 being undeclared when first found at src/main/arithmetic.c:1019 If I fiddle a bit with it later on I also get errors about log1p bein undeclared. Any idea what should I look for? I am using R 1.9.0 in

Hello all, Just joined this mailing list -- not sure if this is the right list to send this question, but I have a question about cross-compiling R. I am working with R-1.9.1.tgz. It may just be with my version of mingw32, but it seems that expm1 is not defined, so I tried to ensure that HAVE_EXPM1 was #undef'ed before cross-compiling. The problem is that, in <include/Rmath.h> if

Please note that you need to report your platforms (as per the posting guide), as the C function starts #ifdef HAVE_COSPI #elif defined HAVE___COSPI double cospi(double x) { return __cospi(x); } And AFAICS the system versions on Solaris and OS X behave the same way as R's substitute. On 01/12/2016 09:12, Martin Maechler wrote: >>>>>> Martin Maechler <maechler

Hi, I'm currently in the process of writing an R-installation SOP for my company. As part of that process I'm using the recommendations from the 'R Installation and Administration' document, section 3.2, "Testing an installation". This is done on an XP machine, using the latest binary of 2.11.0. The binary is downloaded and then installed from the installer. I then

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

Dear R users, according the help(log), the function log2(x) should give the natural logarithm of x. I expect in case of x=2 to to get 0.6931, however, R gives me 1 as a result. Similar, logb(2,2) gives 1 again. I'm wondering if I have missed something ? Yours Frank -- Frank Mattes, MD e-mail: f.mattes at ucl.ac.uk Department of Virology fax 0044(0)207 8302854 Royal Free Hospital

There is a small typo in the Source section of the help page for log1p: Source: 'log1p' and 'expm1' may be taken from the operating system, but if not available there are based on the Fortran subroutine 'dlnrel' there -> they Jen > sessionInfo() R version 3.0.2 (2013-09-25) Platform: x86_64-unknown-linux-gnu (64-bit) locale: [1] LC_CTYPE=en_US.UTF-8

If pi were stored and computed to infinite precision then yes we would expect tan(pi/2) to be NaN, but computers in general and R specifically don't store to infinite precision (some packages allow arbitrary (but still finite) precision) and irrational numbers cannot be stored exactly. So you take the value of the built in variable pi, which is close to the theoretical value, but not exactly

Hi, pbirthday(, coincident = 2) starts to issue warnings (see (*) below) for larger number of classes (R 4.0.0, R-devel ./src/library/stats/R/birthday.R:47). The default coincident = 2 is computed as 1 - prod((c:(c - n + 1))/rep(c, n)) where c = classes. Using exp(log(...)), one can derive the return value if(n > 0) 1 - exp(sum(log1p(-(0:(n-1))/c))) else 0. Simplifying this a bit further one

I am having a slight problem with probabilities. To calculate the final probability of an event p(F), we can take the product of the chance that each independent event that makes p(F) will NOT occur. So... p(F) = 1- ( (1-p(A)) * (1-p(B)) * (1-p(C))...(1-p(x)) ) If the chance of an event within the product occurring remains the same, we can therefore raise this probability to a power of the

I have never found the R symbolic differentiation helpful because my functions are typically quite complicated, but was prompted by Steve Ellison's suggestion to try it out in this case: ################# reprex (see reprex package) graphdta <- read.csv( text = "t,c 0,100 40,78 80,59 120,38 160,25 200,21 240,16 280,12 320,10 360,9 400,7 ", header = TRUE ) nd <- c( 100, 250,