I have multiple data.frames that I want to rbind together using R. I also have a character vector with the names of each of these data.frames. What I’m looking to do is use this character vector to determine which data.frames to bind together. For example, I have 5 similar data.frames below and I want to… Read More Combining data.frames in R based off a character list
aa <- data.frame(a= c(1,1,2,3,4), b = c(5,3,2,6,1)) bb <- data.frame(a= c(1,1,6,7,4), c = c(4,3,7,2,1)) I want to merge aa and bb by the rows, however, when I use the rbind() function, it gives me an error that "the numbers of columns of arguments do not match". The final format that I want keeps all the… Read More R merge two dataframes by rows with some similar but also different columns
Consider the minimal working example raw_list <- list(1, 2) process_list <- function(item) { if(item == 1) { return(list(c(1, 1), c(2, 2))) } else { return(c(3, 3)) } } processed_list <- lapply(raw_list, process_list) df <- do.call(rbind, processed_list) processed_list is [[1]] [[1]][[1]] [1] 1 1 [[1]][[2]] [1] 2 2 [[2]] [1] 3 3 and df is [,1]… Read More How to unnest lists in a list into a list?
I’m trying to find the equivalent of tidyr::unnest() for a data.table with multiple nested columns: MT <- as.data.table(mtcars) MT_NEST_MULT <- MT[, .(data1 = .(.SD[, .(mpg, hp)]), data2 = .(.SD[, !c("mpg", "hp")])), by = .(cyl, gear)] cyl gear data1 data2 8 3 <S3: data.table> <S3: data.table> 8 5 <S3: data.table> <S3: data.table> 6 4 <S3: data.table>… Read More Un-nesting multiple columns with data.table in R
i would much appreciate some advice Im currently doing an elastic net regression where I am using a for loop to apply 10 diferents value of alpha from 0 to 1, the thing is that when I ask the results of the models it is only giving me the result of alpha=1, here is my… Read More Elastic net regression model with loops is not giving me list of results based on alpha R
I want to make a new column that is the sum of all the columns that start with "m_" and a new column that is the sum of all the columns that start with "w_". Unfortunately it is not every nth column, so indexing all the odd and even columns won’t work. columnnames <- c("m_16",… Read More R: Sum of all the columns that start with
Is there a way to sample X number of random rows and X non-random rows in a single sample? For example, I want to get 1,000 samples of 4 rows of iris. I want to randomly sample 3 rows of iris and the fourth row will be the same one in each sample (this is… Read More Sampling randomly and non-randomly in one sample
I often find myself creating two similar data frames that I’d like to rbind together but keep track of which one each row came from with a distinguishing column. My typical motif has been new_df <- rbind( cbind(df1, id="A"), cbind(df2, id="B") ) which collapses nicely into a single line for readability but feels clunky and… Read More One-liner to concatenate two data frames with a distinguishing column?
for dataframe below, df <- data.frame(id = c(rep(101, 4), rep(202, 3)), status = c("a","b","c","d", "a", "b", "c"), wt = c(100,200,100,105, 20,22,25), ht = c(5.3,5.2,5,5.1, 4.3,4.2,4.1)) df id status wt ht 1 101 a 100 5.3 2 101 b 200 5.2 3 101 c 100 5.0 4 101 d 105 5.1 5 202 a 20 4.3… Read More How to insert rows in specific indices of dataframe containing sum of few rows above only in R pipe dplyr
I have a DB like this: a <-c(4, 2, 10, 2, 10, 6, 2) b <-c(4, 6, 70, 8, 18, 4, 3) rbind(a,b) I can create something like this: x <- (4, 4, 2, 6, 10, 70, 2, 8, 10, 18, 6, 4, 3) A DB that contains a and b order in this way,… Read More Change order value