Hi there, I am new to R and keen to learn but am finding myself particularly stuck on what seems to be a relatively straightforward idea. I have 2 dataframes. The first (ants) is data pertaining to a number of sites, each site has a unique ID, some sites have more than one row of data. It look like this: Site Date T...
Hi I have a data.frame with 10 rows and 3 columns a b c 1 1 201 1 2 2 202 1 3 3 203 1 4 4 204 1 5 5 205 4 6 6 206 5 7 7 207 4 8 8 208 4 9 9 209 8 10 10 210 5 I want to delete all rows where the same value in the column "c" repeated less than 3 times. In this example I want to remove rows 6, 9 and 10. (my real d...
I'm new to R. I have a a Data.frame with a column called "Symbol". Symbol 1 "IDEA" 2 "PFC" 3 "RPL" 4 "SOBHA" I need to store its values as a vector(x = c("IDEA","PFC","RPL","SOBHA")). Which is the most concise way of doing this? Thanks in Advance ...
Hi, Below are the first five rows of the imported data in R: data[1:5,] user event_date day_of_week 1 00002781A2ADA816CDB0D138146BD63323CCDAB2 2010-09-04 Saturday 2 00002D2354C7080C0868CB0E18C46157CA9F0FD4 2010-09-04 Saturday 3 00002D2354C7080C0868CB0E18C46157CA9F0FD4 2010-09-07 Tuesday 4 00002D2354C7080C0868CB0E18C46157...
Hello, I ran into a little problem using R… In the following data frame test <- data.frame(v1=c(rep(1,3),rep(2,3)),v2=0) I want to change values for v2 in the rows where v1 is 1. test[test$v1==1,"v2"] <- 10 works just fine. test v1 v2 1 1 10 2 1 10 3 1 10 4 2 0 5 2 0 6 2 0 However, I need to do that in a function. ...
I have a data.frame which has multiple columns. One of the columns is time and is thus non-decreasing. Rest of the columns contain observations recorded at the time given by the time specified in a certain row of the data.frame. I want to select a window of time, say "x" seconds, and calculate the average (or for that matter any functio...
Hi all, I've got transactional data from a SQL query which I turn into a data frame. The first column of the df contains UNIX timestamps (format="%Y/%d/%m %H:%M") which I would like to use to create a graphics plot using par to display 1 unique lineplot per date. At the moment I am fumbling around with splitting column 1 and comparing wi...
I have a problem while using a subset of a data.frame in R. The subset gets created and displayed correctly, but when I try to plot it using qplot(), the rows which were not selected by the subset() also get shown along one axis. The actual file I am reading in is a web server log, but I have created a small example to illustrate my pr...
Hi, I'm relatively new to R, and was wondering the most efficient way to iteratively construct a dataframe (one row at a time, the number of iterations "n" and the length of each row "l" are known beforehand). Create empty dataframe, add a row each iteration Preallocate n x l dataframe, modify a row each iteration Preallocate n x l mat...
What is the most memory efficient and easiest (yes, I know those are sometimes mutually exclusive) way to create an R data frame then save it to an .Rdata file using Java? Go easy on me though, I'm not a Java developer. ...