similar to: arithmetic and logical operators

Hi, I'm using the '%%' operator in some code, and am running into the following erroneous outcome: > 1.2 %% 0.2 [1] 0.2 Unless I'm very mistaken, the result should be 0 (indeed, 12 %% 2 does result in 0). Furthermore: > 1.20000000000000001 %% 0.2 [1] 0.2 > (1.2+1e17) %% .2 [1] 0 Warning message: probable complete loss of accuracy in modulus (Warning

Dear colleagues Please could someone kindly explain the following inconsistencies I've discovered when performing logical calculations in R: 8.8 - 7.8 > 1 > TRUE 8.3 - 7.3 > 1 > TRUE Thank you, Emma Jane [[alternative HTML version deleted]]

Do you heve any idea why I get after this instruction everywhere false? > seq (0, 1, by=0.1) == 0.3 [1] FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE But after different step it's ok: > seq(0, 1, by=0.1) == 0.4 [1] FALSE FALSE FALSE FALSE TRUE FALSE FALSE FALSE FALSE FALSE FALSE -- View this message in context:

Hi, there, I cannot get accurate value for calculation. for example: ld<-sqrt(1*0.05*0.95*0.05*0.95) 0.05*0.95-ld=-6.938894e-18 0.05*0.95-ld==0 is False. I met this problem in my program, how can I handle it. Thanks. xj.

Full_Name: jan hattendorf Version: 2.9.0 OS: XP Submission from: (NULL) (213.3.108.185) I get an incorrect result for (41/10-1/10)%%1 [1] 1 The error did not occur with other numbers than 41 (1, 11, 21, 31, 51, ...) test <- rep(NA, 1000) for(i in 1:1000){ test[i] <- i/10-1/10 } test[test%%1==0]

To the R development team: First of all, thank you so much for maintaining wonderful R software. Perhaps, Dr. Ahn has just reported an error on the wilcox.test() function, and suggesting that an error may arise from abs() and rank(). I just had a quick check that the problem may come from the precision of the results of arithmetic functions. 87.7-89.1+1.4 # > 87.7-89.1+1.4 # [1]

Hi, I'm having trouble with the "which" or the "seq" function, I'm not sure. Here's an example : > lat=seq(1,2,by=0.1) > lat [1] 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 > which(lat==1) [1] 1 > which(lat==1.1) [1] 2 > which(lat==1.2) [1] 3 > which(lat==1.3) [1] 4 > which(lat==1.4) [1] 5 > which(lat==1.5) [1] 6 >

Hello everyone,           I have a basic question regarding logical operators. > x<-seq(-1,1,by=0.02) > x   [1] -1.00 -0.98 -0.96 -0.94 -0.92 -0.90 -0.88 -0.86 -0.84 -0.82 -0.80 -0.78  [13] -0.76 -0.74 -0.72 -0.70 -0.68 -0.66 -0.64 -0.62 -0.60 -0.58 -0.56 -0.54  [25] -0.52 -0.50 -0.48 -0.46 -0.44 -0.42 -0.40 -0.38 -0.36 -0.34 -0.32 -0.30  [37] -0.28 -0.26 -0.24 -0.22 -0.20 -0.18 -0.16

(I use R 2.9.1 with win XP) If I run this code: seq(-0.1,.9, by = .05)[seq(-0.1,.9, by = .05) <= 0.5] I get this output: [1] -0.10 -0.05 0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35 0.40 0.45 Why is 0.50 not in the results ? (It seems that it gives a slightly bigger number then 0.5 but I don't understand why it does that) Where as if I try: seq(-0.1,.9, by = .05)[seq(-0.1,.9, by = .05) <=

Hi all, In checking my R codes, I encountered the following problem. Is there a way to fix this? I tried to specify options(digits=). I did not fix the problem. Thanks so much for your help! Hanna > cdf(pmass)[2,2]==pcum[2,2][1] FALSE> cdf(pmass)[2,2][1] 0.9999758> pcum[2,2][1] 0.9999758 [[alternative HTML version deleted]]

Hi R, I have certain checkings, which gives FALSE, but actually it is true. Why does this happen? Note that the equations that I am checking below are not even the case of recurring decimals... > 1.4^2 == 1.96 [1] FALSE > 1.2^3==1.728 [1] FALSE Thanks in advance, Shubha Shubha Karanth | Amba Research Ph +91 80 3980 8031 | Mob +91 94 4886 4510 Bangalore * Colombo *

> length(sample(25000, 25000*(1-.55))) [1] 11249 > 25000*(1-.55) [1] 11250 > length(sample(25000, 11250)) [1] 11250 > length(sample(25000, 25000*.45)) [1] 11250 So the question is, why do I get 11249 out of the first command and not 11250? I can't figure this one out. Thanks Cory [[alternative HTML version deleted]]

Hello, here is the version of R that I use : > version _ platform i486-pc-linux-gnu arch i486 os linux-gnu system i486, linux-gnu status major 2 minor 3.1 year 2006 month 06 day 01 svn rev 38247 language R version.string Version 2.3.1 (2006-06-01) And here is one of the sequences of

Hello dear r-help group I am turning for you for help with FAQ number 7.31: "Why doesn't R think these numbers are equal?" http://cran.r-project.org/doc/FAQ/R-FAQ.html#Why-doesn_0027t-R-think-these-numbers-are-equal_003f *My story* is this: I wish to run many lm predictions and need to have them run fast. Using predict.lm is relatively slow, so I tried having it run faster by

With floating point numbers I'm seeing 'cut' putting values in the wrong bands. An example below places 0.3 in (0.3,0.6] i.e. 0.3 > 0.3. > x = 1:5*.1 > x [1] 0.1 0.2 0.3 0.4 0.5 > cut(x, br=c(0,.3,.6)) [1] (0,0.3] (0,0.3] (0.3,0.6] (0.3,0.6] (0.3,0.6] Levels: (0,0.3] (0.3,0.6] I'm sure this is probably the same issue documented in the FAQ (7.31 Why doesn't R

Hi, Check the FAQ 7.31 https://cran.rstudio.com/doc/FAQ/R-FAQ.html#Why-doesn_0027t-R-think-these-numbers-are-equal_003f And read the posting guide too... https://www.r-project.org/posting-guide.html HTH, Ivan -- Dr. Ivan Calandra TraCEr, Laboratory for Traceology and Controlled Experiments MONREPOS Archaeological Research Centre and Museum for Human Behavioural Evolution Schloss Monrepos 56567

Dear list, I have observed a weird behaviour from R --- apologies if I am missing something obvious! df3f826f28 df3f826f28 Say you type in R: >c.preec <- 10074 >c.gd <- 2200 >p1 <- .2 >c.neo <- p1*9451 + (1-p1)*3883 >n.preec <- 3710 >n.gd <- 2650 >n.neo <- 2120 >n.pcos <- 53000 >unit.met <- 94 >cost.met <- 94*n.pcos >effect <-

Hi, I apologize if there is a simple answer to this question that I've missed. I did search the mailing list but I might not have used the right keywords. Why does sum(A3^2) give the result of 1, but sum(A3^2)==1 give the result of FALSE? > A3<-matrix(nrow=3,c(1/(2^.5),1/(2^.5),0)) > A3 [,1] [1,] 0.7071068 [2,] 0.7071068 [3,] 0.0000000 > sum(A3^2) [1] 1 >

Dear R Helpers, I am trying to extract the modulus from divisions by a sequence of fractions. I noticed that %% seems to behave inconsistently (to my untutored eye), thus: > 0.1%%0.1 [1] 0 > 0.2%%0.1 [1] 0 > 0.3%%0.1 [1] 0.1 > 0.4%%0.1 [1] 0 > 0.5%%0.1 [1] 0.1 > 0.6%%0.1 [1] 0.1 > 0.7%%0.1 [1] 0.1 > 0.8%%0.1 [1] 0 > 0.9%%0.1 The modulus for 0.1, 0.2, 0.4 and 0.8 is

Full_Name: Suzi Alves Camey Version: 2.7.2 OS: Submission from: (NULL) (143.54.37.254) Using the commands bellow I expected that the answer is TRUE, but it is FALSE! P_exposicao=.9 (1-P_exposicao)==.1