How to remove all whitespace from a string?
So ” xx yy 11 22 33 ” will become “xxyy112233”. How can I achieve this? 9 Answers 9
r-faq
How to find common elements from multiple vectors?
Can anyone tell me how to find the common elements from multiple vectors? a <- c(1,3,5,7,9) b <- c(3,6,8,9,10) c <- c(2,3,4,5,7,9) I … Read more
Remove duplicated rows
I have read a CSV file into an R data.frame. Some of the rows have the same element in one of the columns. … Read more
Error: could not find function … in R
This is meant to be a FAQ question, so please be as complete as possible. The answer is a community answer, so feel … Read more
Speed up the loop operation in R
I have a big performance problem in R. I wrote a function that iterates over a data.frame object. It simply adds a new … Read more
Numbering rows within groups in a data frame
Working with a data frame similar to this: set.seed(100) df <- data.frame(cat = c(rep(“aaa”, 5), rep(“bbb”, 5), rep(“ccc”, 5)), val = runif(15)) df … Read more
Reshaping data.frame from wide to long format
I have some trouble to convert my data.frame from a wide table to a long table. At the moment it looks like this: … Read more
Use of ~ (tilde) in R programming Language
I saw in a tutorial about regression modeling the following command: myFormula <- Species ~ Sepal.Length + Sepal.Width + Petal.Length + Petal.Width What … Read more
ggplot2 line chart gives “geom_path: Each group consist of only one observation. Do you need to adjust the group aesthetic?”
With this data frame (“df”): year pollution 1 1999 346.82000 2 2002 134.30882 3 2005 130.43038 4 2008 88.27546 I try to create … Read more
Use dynamic name for new column/variable in `dplyr`
I want to use dplyr::mutate() to create multiple new columns in a data frame. The column names and their contents should be dynamically … Read more