similar to: Surprising Behavior of 'tapply'

Dear all, given I have data in a data.frame which indicate the number of people in a specific year at a specific age: n <- 10 mydf <- data.frame(yr=sample(1:10, size=n, replace=FALSE), age=sample(1:12, size=n, replace=FALSE), no=sample(1:10, size=n, replace=FALSE)) Now I would like to make a matrix with (in this simple example) 10 columns (for the

Dear all, given I have a data.frame in a format like this mydf <- data.frame(age=rep(1:3,5), year=c(rep(1996,3), rep(1997,3), rep(1998,3), rep(1999,3), rep(2000,3)), income=1:15) mydf Now I convert it to some 2D-frequency table like this: mymatrix <- tapply(X=mydf$income, INDEX=list(mydf$age, mydf$year),

Dear R-Helpers, I have a matrix where the first column is known. The second column is the result of multiplying this first column with a constant "const". The third column is the result of multiplying the second column with "const"..... So far, I did it like this (as a simplified example): nr.of.columns <- 4 myconstant <- 27.5 mymatrix <- matrix(numeric(0), nrow=5,

Hi All, I'm fiddling with an program to read a text file containing periods that SAS uses for missing values. I know that if I had the original SAS data set instead of a text file, R would handle this conversion for me. Data frames do not allow missing values in their indices but vectors do. Why is that? A search of the error message points out the problem and solution but not why they

Dear All, I have these data: exampledata <- c("This is one item", "This is Another One", "And so is This") I would like to find each occurence of a blank space followed by a Capital Letter and replace it by a blank space, a left curly brace, the respective Capital Letter, and then a right curly brace. I thought the following will do: gsub(pattern = "

Dear R-Users, given you have been teaching R to students (grad level, mainly social science background, no previous programming experience, 80% know SPSS), what are your experiences concerning the style of teaching? Do you prefer to stand in front of the class like in "normal" lectures and you show them slides? Or do you you explain some concept (for example things like

Dear all, I have a population with three age-classes, at time t=0 the population is: n.zero <- c(1,0,0) I have a transition matrix A which denotes "fertility" and "survival": A <- matrix(c(0,1,5, 0.3,0,0, 0,0.5,0), ncol=3, byrow=TRUE) To obtain the population at t=1, I calculate: A %*% n.zero To obtain the population t=2, I calculate: A %*% (A %*% n.zero) ... and so

Hi, > [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Corey Powell > > Do you know of any references that verify the accuracy of R > for basic statistical calculations and tests. The results of > these studies should indicate that R results are the same as > the results of other statistical packages to a certain number > of decimal places on some benchmark

I have a dataframe with names in the first column and wait times between decisions in the second column. Since individuals make multiple decisions, I want the average for each individual. For example, the data might look like this name wtime jo 1 jo 2 jo 1 jo 3 tim 3 tim 2 tim 2 ro 1 ro 2 etc. I'm hoping there is something like mean(dataname$wtime[name]) which will just

Dear all, This is a rather lengthy message, but I don't know what I made wrong in my real example since the simple code works. I have two variables a, b and a function f for which I would like to calculate all possible combinations of the values of a and b. If f is multiplication, I would simply do: a <- 1:5 b <- 1:5 outer(a,b) ## A bit more complicated is this: f <-

Dear all, This is a rather lengthy message, but I don't know what I made wrong in my real example since the simple code works. I have two variables a, b and a function f for which I would like to calculate all possible combinations of the values of a and b. If f is multiplication, I would simply do: a <- 1:5 b <- 1:5 outer(a,b) ## A bit more complicated is this: f <-

Hello, If a matrix with 5 columns has been defined and the first two columns need to be sorted in ascending order, how can this be achieved whilst ensuring the other 3 columns data are in relative position to the sorted columns? Glen Jones [[alternative HTML version deleted]]

Dear all, I'd appreciate any hints how to arrange some plots. I have three plots. I would like to arrange them in the following order: - Plot 1 and Plot 2 should be in the upper row - Plot 3 should be in the lower row but centered in the middle. I hope the following sketch will help understanding my problem ================ | === === | || P1| |P2 | | || | | | | | === === |

Hello, I'm trying to do bar plot where 'sex' will be the category axis and 'occupation' will represent the bars and the clusters will represent the mean 'income'. sex occupation income 1 female j 12 2 male b 34 3 male j 22 4 female j 54 5 male b 33 6

We can't post images here so I've put up a web page to show off a neat little animation in R: http://www.geocities.com/robsteele/ Adios!

Dear all, in the coming Winter Semester, I will be a teaching assistant for a course in Survival Analysis. My job will be to do the lab sessions. The software used for these lab sessions will be R. Most of the students have a background in social sciences and the only stats package they used so far is most likely SPSS. So I assume they might be quite surprised the first time they see R

Dear all, in the first paragraph in Section 4.3.2 of the "R Data Import/Export Manual", it is written 'We havew tested...'. Most likely it should be 'We have tested...' It is just such a minor thing that I was unsure whether to submit a bug report. I use now R 2.2.1 on Win32 but I guess this is independent of the platform and version. Best, Roland P.S. Thanks for

Can somebody remember me which is the command to erase columns from a data frame? Thanks Michele ___________________________________ http://it.seriea.fantasysports.yahoo.com/

Dear all, my question might be a bit off-topic. Is there anything like a standard textbook on statistical programming? With that I don't mean anything like MASS, S Programming, Programming with Data, ... (no offense meant, they are fantastic books and each of those three helped me a great deal). Rather in the direction of the "Numerical Recipes" Series addressing how to implement

Dear all, I installed Mandrakelinux 10.1 (community) on my notebook. Before, I used Mandrakelinux 9.1 (and later 10.0 as an update). Now I wanted to compile, as before, R. In the beginning, nothing worked but it seemed to be the problem of GCC 3.4.1 which was shipped with my distribution. After downloading and compiling GCC 3.4.3 everything went smoothly during the compilation of R. The problem