Create a dataframe by fixing rows in one column and repeating other columns

Question

Lets say I have three variables:

var1<-c(101,102,103,104)
var2<-c("AB","XY")
var3<-c(1,2)

X<-expand.grid(var1,var2,var3)
X

Above code gives this output

   Var1 Var2 Var3
1   101   AB    1
2   102   AB    1
3   103   AB    1
4   104   AB    1
5   101   XY    1
6   102   XY    1
7   103   XY    1
8   104   XY    1
9   101   AB    2
10  102   AB    2
11  103   AB    2
12  104   AB    2
13  101   XY    2
14  102   XY    2
15  103   XY    2
16  104   XY    2

What I need is the series below in which for each row value in var1 we have corresponding values in var2 and var3.

   Var1 Var2 Var3
1   101  AB  1
2   101  XY  2
3   102  AB  1
4   102  XY  2
5   103  AB  1
6   103  XY  2
7   104  AB  1
8   104  XY  2

Answer 1

If you are already using the tidyr package, you can use the crossing function. For example

tidyr::crossing(var1, tibble::tibble(var2, var3))
#    var1 var2   var3
#   <dbl> <chr> <dbl>
# 1   101 AB        1
# 2   101 XY        2
# 3   102 AB        1
# 4   102 XY        2
# 5   103 AB        1
# 6   103 XY        2
# 7   104 AB        1
# 8   104 XY        2