similar to: seq(...) strange logical value

Hello:I am trying to match the value 0.3 in the sequence seq(.2,.3). I get > 0.3 %in% seq(from=.2,to=.3) [1] FALSE Yet > 0.3 %in% c(.2,.3) [1] TRUE For arbitrary sequences, this "invisible .3" has been problematic. What is the best way to work around this? Thank you. Dan [[alternative HTML version deleted]]

Perhaps somebody could clarify for me if the following is a floating point matter or otherwise, and how am I to correct for it? > floor(100*.1) [1] 10 > 100*(1.0-.9) [1] 10 > floor(100*(1-0.9)) [1] 9 Thanks! Michael _______________________________________________________ Michael Folkes Salmon Stock Assessment Canadian Dept. of Fisheries & Oceans Pacific Biological Station

Hello! I stumbled upon something odd that took a while to track down, and I wanted to run it by here to see if I should submit a bug report. For randomly generated numbers (from a variety of distributions) rounding them to specifically 2 digits and then multiplying them by 100 produces strange results on about 8% of cases. The problematic numbers display as I would have expected, but do not

Hi all, Is there any problem of precision when using seq?. For example: x<- seq(0,4,0.1) x[4]=0.3 BUT: x[4]-0.3=5.551115e-17 It means when I use this condition within an if clause, it does not find values with 0.3 for x[4] as it is not precisely 0.3. Is there any bug in seq() ? -- View this message in context: http://r.789695.n4.nabble.com/Inconsistency-using-seq-tp4633739.html Sent from

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]

> 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]]

Hi, This is really strange. Can anyone help explain what's going on here (on 3 and 7)? > targets <- seq(from=.1, to=.9, by=.1) > targets[1]==.1 [1] TRUE > targets[2]==.2 [1] TRUE > targets[3]==.3 [1] FALSE > targets[4]==.4 [1] TRUE > targets[5]==.5 [1] TRUE > targets[6]==.6 [1] TRUE > targets[7]==.7 [1] FALSE > targets[8]==.8 [1] TRUE >

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]]

(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, 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.

Hi, Today I was flabbergasted to see something that looks like a rounding error in the very basic seq function in R. > a = seq(0.1,0.9,by=0.1) > a [1] 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 > a[1] == 0.1 [1] TRUE > a[2] == 0.2 [1] TRUE > a[3] == 0.3 [1] FALSE It turns out that the alternative > a = (1:9)/10 works just fine. Are there any good guides out there on how to deal

Full_Name: Johannes Prix Version: 2.1.1 OS: WinXP, SuSE Linux Submission from: (NULL) (137.208.41.195) The seq-command produces unnescessary inaccurate results, which can be extremely annoying. I absolutely do not see the nescessity of numerical garbage to appear in the following simple case. E.g. try this: > seq ( 61.55 , 62.00 , by=0.01 ) - round ( seq ( 61.55 , 62.00 , by=0.01 ) ,

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 >

Full_Name: Raimon Massanet Version: 2.9.2 OS: Linux Ubuntu 8.10 Submission from: (NULL) (147.83.71.76) # Hi there. # I'm not sure whether or not this is a bug. # But it surely is an unexpected behaviour. V <- seq(from=0,to=1,by=0.1) # Should generate a sequence with a step of 0.1 V==0 # [1] TRUE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE FALSE # Ok! V==0.1 # [1] FALSE

Hi all, please see my code: > library(zoo) > a <- as.yearmon("March-2010", "%B-%Y") > b <- as.yearmon("May-2010", "%B-%Y") > > nn <- (b-a)*12 # number of months in between them > nn [1] 2 > as.integer(nn) [1] 1 What is the correct way to find the number of months between "a" and "b", still

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

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]]

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

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

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 *