r - How does plyr merge two columns of different data.frames with same names but different values

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

从 rbind.fill 的帮助页面：

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

所以我希望它能够填充与 NA 不匹配的列。这里也没有必要使用do.call()。

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

你期待不同的东西吗？