Output of for loop as rows in a dataframe in R

Question

I have created a for loop which creates a series of vectors, as follows...

(For the sake of simplicity, I have not included my full code)

for (i in vectorname){
a<-(*lots of code!*)
b<-(*lots of code...*)
c<-(*lots of code..*.)
}

I would like the loop to output these vectors in a dataframe by row. Ie row 1 would be the values in vector a, row 2 is the values from vector b...etc). Can anyone advise on how I could do this?

If relevant, I should also note that each vector will contain 11 values (so the df needs 11 columns).

Thank you!

Answer 1

I have created a for loop which creates a series of vectors, as follows...

(For the sake of simplicity, I have not included my full code)

for (i in vectorname){
a<-(*lots of code!*)
b<-(*lots of code...*)
c<-(*lots of code..*.)
}

I would like the loop to output these vectors in a dataframe by row. Ie row 1 would be the values in vector a, row 2 is the values from vector b...etc). Can anyone advise on how I could do this?

If relevant, I should also note that each vector will contain 11 values (so the df needs 11 columns).

Thank you!

Answer 2

library(tidyverse)

ITERATIONS <- 5

# create an empty dataframe
my_df <- data.frame(matrix(ncol=3,nrow=0))
names(my_df) <- c("cyl", "vs", "mpg")
my_df <- my_df %>% 
    mutate(
      cyl = as.integer(cyl),
      vs = as.logical(vs),
      mpg = as.double(mpg)
    )

# run for loop and bind each output as a new row
for (i in 1:ITERATIONS) {

    new_row <- 
        mtcars %>% 
        sample_n(10) %>% 
        summarise(
          cyl = max(cyl),
          vs = all(is.na(vs)),
          mpg = mean(mpg)
        )
    
    my_df <- bind_rows(my_df, new_row)
}

my_df