plyr如何合并两列具有相同名称但不同值的不同data.frames

Question

While merging 3 data.frames using plyr library, I encounter some values with the same name but with different values each in different data.frames.

How does the do.call(rbind.fill,list) treat this problem: by arithmetic or geometric average?

Answer 1

From the help page for rbind.fill:

Combine data.frames by row, filling in missing columns. rbinds a list of data frames 
filling missing columns with NA.

So I'd expect it to fill columns that do not match with NA. It is also not necessary to use do.call() here.

dat1 <- data.frame(a = 1:2, b = 4:5)
dat2 <- data.frame(b = 3:2, c = 8:9)
dat3 <- data.frame(a = 5:6, c = 1:2)

rbind.fill(dat1, dat2, dat3)
   a  b  c
1  1  4 NA
2  2  5 NA
3 NA  3  8
4 NA  2  9
5  5 NA  1
6  6 NA  2

Are you expecting something different?