How do I put one data.frame 'on top of' another?
That is the new number of rows must equal the sum of the two input data
frames.
rbind() does exactly this when the datasets match columns.
I need to stack data.frames where the columns don't match completely and
put missing places where the new column was unavailable before.
A simple example:
top is:
ID WEIGHT
1 66.3
2 52.6
bottom is:
ID BMI
3 21.6
4 23.1
The combined result should be:
all
ID WEIGHT BMI
1 66.3 -
2 52.6 -
3 - 21.6
4 - 23.1
Note that
nrow(all) == nrow(top) + nrow(bottom)
and
columns are the union of the two inputs.
Any suggestions on how to accomplish this would be appreciated.
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