similar to: optimize in very small values

Dear friends - merry Christmas and thanks a lot for much help during the year! In the example below I fail to understand how the calculated value pH is represented in a simple plot - also included. The calculations are useful in practice and likely to be right in principle but I cannot see how this occurs: why a calculated value of 7.4 known as numeric is not simply plotted as such. It

Dear friends - copy paste missed SID <- c() before the first loop - sorry BW Troels Den 25-12-2017 kl. 19:12 skrev Troels Ring: > > Dear friends - merry Christmas and thanks a lot for much help during > the year! > > In the example below I fail to understand how the calculated value pH > is represented in a simple plot - also included. The calculations are > useful

Thanks a lot - formatting the ordinate as ylim=c(4,10) before plotting pH also removed the problem, and options(digits=10) confirmed that pH was not all exactly 7.4 - as I knew. Still I wonder just why R chooses to plot(ATOT,pH) as shown with repeated "7.4" instead of some more detailed representation. Thanks a gain and happy New Year! Troels Den 26-12-2017 kl. 01:03 skrev Bert

Dear friends - occurring in Windows R2.6.2 I am modeling physical chemistry in collaboration with a friend who has preferred working in Excel. I used uniroot, and find a solution to a two buffer problem in acid-base chemistry which I believe is physiologically sensible. Using "goal seek" in Excel my friend found another plausible root, quite close to zero, and a plot of the function

Halo i'm studying chemistry, today we made an experiment and i have to draw a titration kurve for my mess data. we can do it on a mm paper, or we can also use a programe. people from chemistry recomend "R" last year i studied civil eng. and we used Matlab, as I see, R ist very similar to it, but its got other comands. But i think R would be a good help for some exercises. so my

Good afternoon, I have a 63 small .csv files which I process daily, and until two weeks ago they processed just fine and only took a matter of moments and had non noticeable memory problem. Two weeks ago they have reached 318 lines and my script "broke". There are some missing-values in some of the files. I have tried hard many times over the last two weeks to create a

move or copy the directories mass, nnet and class to the library directory - then execute link.html.help() Now execute library(MASS) and data(petrol) Should work. "Troels Ring"

Good morning, I have currently 63 .csv files most of which have lines which look like 01/06/05,23445 Though some files have two numbers beside each date. There are missing values, and currently the longest file has 318 rows. (merge() is losing the head and doing runaway memory allocation - but thats another question - I'm still trying to pin that issue down and make a small repeatable

Dear friends, I was drawing a circle with centrum in (1,-1) and radius 5 to show my girl that the line y=3*x+1 goes through (1,4) and (-2,-5) of the circle, but on Windows XP, R 2.20 the drawing was not good at all, and the known solutions were not shown in the graph. I guess I got it wrong? Is this use not intended ? Best wishes Troels Ring, MD Aalborg, Denmark

Dear friends - I'm using Tinn-R in Windows and find it OK. My son is running MacOS and is just starting using R and I know nothing about MacOS and R but we seem to have difficulties in finding something similar to Tinn for MaC. What are your suggestions? Thanks a lot! Troels Ring, MD Aalborg, Denmark

Dear friends. I have trobpe with path. Below I have tried to paste a path and file name but it will not work > path <- "D:/rw0641/own/own/procedures/GFR_TIME" > path [1] "D:/rw0641/own/own/procedures/GFR_TIME" > path1 <- paste(path,"gfr.txt",sep="/") > path1 [1] "D:/rw0641/own/own/procedures/GFR_TIME/gfr.txt" -- this is good

Dear Friends, I'm using winXP and R 1.7.1 and plotting some data using dates on the x-axis, and wanted to use identify to show some points but was told by identify that the x and y vectors producing a fine graph with 84 points were not equal in length. Below are the Dato for date - and length(Dato) finds 9 but str finds 84 as known. Will identify not work in this context ? Best wishes

Good morning! I've searched the docs etc... Am I doing something wrong or is this a bug? I'm doing a merge of two dataframes and getting extra rows in the resulting dataframe - the dataframes being merged might have NAs... count <- 10 nacount <- 3 a1 <- as.data.frame(as.Date("2005-06-01")+0:(count-1)) names(a1) <- "mdate" a1$value <- runif(count)

Hi, I'm using windows xp and R 2.8.0 - I wonder what is the command to put in a script that has the same effect as when in a plot you choose menu "History" and "Recording". Best wishes Troels -- Troels Ring - - Department of nephrology - - Aalborg Hospital 9100 Aalborg, Denmark - - +45 99326629 - - tring at gvdnet.dk

Dear friends - below is a subset of a much larger material showing two ways of generating two "lines". The intention is to have the colour reflect a variable, pH, but the legend is disturbed. The little part marked "3" above the colour scale is unwelcome. Why did it appear? How could I avoid it? I'm on Windows 7, R version 3.4.1 (2017-06-30) -- "Single

Dear friends - I hope you will accept a naive question on lm: R version 3.4.1, Windows 10 I have 204 "baskets" of three types corresponding to factor F, each of size from 2 to 33 containing measurements, and need to know if the standard deviation on the measurements in each basket,sdd, is different across types, F. Plotting the observed sdd versus the sizes from 2 to 33, called

Dear friends - I have a function for the charge in a fluid (water) buffered with HEPES and otherwise only containing Na and Cl so that [Na] - [Cl] = SID (strong ion difference) goes from -1 mM to 1 mM. With known SID and total HEPES concentration I can calculate accurately the pH if I know 3 pK values for HEPES by finding the single root with uniroot Now, the problem is that there is some

Dear friends - I have a data.frame with "," instead of "." and found the discussion http://r.789695.n4.nabble.com/How-to-replace-all-commas-with-semicolon-in-a-string-tt4721187.html#a4721192 so copying the code of Ulrik(I hope:-)) I tried (making some data) AX <-

Dear friends - I'm on winXP, R 2.71 - I have with some help dveloped this multivariate normal model, which gives very plausible results in WinBUGS even without any initial values specified. However, when I then try to run the same model via the bugs function in R2WinBUGS with inits specified as inits=NULL the program stops in a dead end. So I have tried to make inits for the bugs function

Dear friends, I found the thread on this subject this summer but wonder whether it has been taken any further. I have an important medical problem where X is computed from a three independent and complicated measurements (exchangeable sodium and potassium and total body water - i.e. X = (Nae+Ke)/TBW ) and Y is serum sodium concentration (all data in Edelman, JCI 1958). I have the individual