How do I append an entire column to the end of another column in r?

Question

I have col3 and col4, both have 5000 rows. I want to make a new column that has 10,000 rows, the first 5000 being col3 and the second 5000 being col4. Or if it's easier they do not actually need to be in order.

Answer 1

are these vestors? A reproducible example would be nice, but some variation of this should work

new_col <- rbind(col3,col4)

Answer 2

Let's first create a sample dataset (as you haven't given)

set.seed(50)
df <- data.frame(col3 = runif(500),
                 col4 = runif(500))

> head(df)
        col3      col4
1 0.70872710 0.1396443
2 0.43765986 0.6179266
3 0.20000490 0.8179890
4 0.76706599 0.2320035
5 0.51316189 0.9072317
6 0.04470388 0.2108911

Nor proceed to append like this (Note you have to create this is as new data frame as previous one has lesser rows than required)

df_new <- data.frame(new_col = c(df$col3, df$col4))

> (tibble(df_new))
# A tibble: 1,000 x 1
   new_col
     <dbl>
 1  0.709 
 2  0.438 
 3  0.200 
 4  0.767 
 5  0.513 
 6  0.0447
 7  0.700 
 8  0.646 
 9  0.0420
10  0.108 
# ... with 990 more rows

In case, you have other columns in data which you have to preserve along with this append, then proceed as follows

set.seed(50)
df <- data.frame(id = 1:500,
                 col3 = runif(500),
                 col4 = runif(500))

(tibble(df))
# A tibble: 500 x 3
      id  col3   col4
   <int> <dbl>  <dbl>
 1     1 0.540 0.0111
 2     2 0.522 0.509 
 3     3 0.371 0.803 
 4     4 0.526 0.274 
 5     5 0.342 0.922 
 6     6 0.450 0.512 
 7     7 0.383 0.698 
 8     8 0.651 0.0556
 9     9 0.491 0.748 
10    10 0.677 0.728 
# ... with 490 more rows

#Process of append
library(dplyr)

df %>% pivot_longer(cols = c(col3, col4)) %>% select(-name)

# A tibble: 1,000 x 2
      id  value
   <int>  <dbl>
 1     1 0.540 
 2     1 0.0111
 3     2 0.522 
 4     2 0.509 
 5     3 0.371 
 6     3 0.803 
 7     4 0.526 
 8     4 0.274 
 9     5 0.342 
10     5 0.922 
# ... with 990 more rows