Using R or Excel, what is the easiest way to convert a frequency table into a vector of values?
E.g., How would you convert the following frequency table
Value Frequency
1. 2
2. 1
3. 4
4. 2
5. 1
into the following vector?
1, 1, 2, 3, 3, 3, 3, 4, 4, 5
In R, you can do it using the repcommand:
tab <- data.frame(value=c(1, 2, 3, 4, 5), freq=c(2, 1, 4, 2, 1))
vec <- rep(tab$value, tab$freq)
This gives following result:
> tab
value freq
1 1 2
2 2 1
3 3 4
4 4 2
5 5 1
> vec
[1] 1 1 2 3 3 3 3 4 4 5
For details, see the help file for the repcommand by typing ?rep.
Obviously in R it's simpler.
In Excel I would use a helper column (if the value is in A1):
value freq help
1 1 2 =REPT(A2 & ", ",B2)
2 2 1 =C1 & REPT(A3 & ", ",B3)
3 3 4 (drag or copy from upper cell)
4 4 2 (drag or copy from upper cell)
5 5 1 (drag or copy from upper cell)
=LEFT(C6, LEN(C6)-1)
In C7 you have your result
