How can I rbind vectors matching their column names?
rbind does not check for column names when binding together vectors:
l = list(row1 = c(10, 20), row2 = c(20, 10))
names(l$row1) = c("A", "B")
names(l$row2) = c("B", "A")
l
$row1
A B
10 20
$row2
B A
20 10
rbind(l$row1, l$row2)
A B
[1,] 10 20
[2,] 20 10
How can I produce this matrix from a number of list elements, insuring the column names are correctly matched across rows:
A B
[1,] 10 20
[2,] 10 20
Answer
It seems that in current versions of R (I have version 3.3.0), rbind has the capacity to to join two data sets with the same name columns even if they are in different order.
df1 <- data.frame(a = c(1:5), c = c(LETTERS[1:5]),b=c(11:15))
df2 <- data.frame(a = c(6:10), b = c(16:20),c=c(LETTERS[6:10]))
rbind(df1,df2)
a c b
1 1 A 11
2 2 B 12
3 3 C 13
4 4 D 14
5 5 E 15
6 6 F 16
7 7 G 17
8 8 H 18
9 9 I 19
10 10 J 20