合并两个数据框，保留所有列 [英] Combining two dataframes keeping all columns

问题描述

我想做的是合并2个数据帧，保留所有列(在下面的示例中未完成)，并在数据帧中有不常见变量的地方输入零.

What I would like to do is combine 2 dataframes, keeping all columns (which is not done in the example below) and input zeros where there are gaps in the dataframe from uncommon variables.

这似乎是plyr或dplyr主题.但是，plyr中的完全联接不会保留所有列，而左联接或右联接不能保留我想要的所有行.查看dplyr速查表( http://www .rstudio.com/wp-content/uploads/2015/02/data-wrangling-cheatsheet.pdf )，full_join似乎是我需要的功能，但R成功加载包后无法识别此功能.

This seems like a plyr or dplyr theme. However, a full join in plyr does not keep all of the columns, whilst a left or a right join does not keep all the rows I desire. Looking at the dplyr cheatsheet (http://www.rstudio.com/wp-content/uploads/2015/02/data-wrangling-cheatsheet.pdf), a full_join seems to be the function I need, but R does not recognise this function after succesfully loading the package.

例如:

col1 <- c("ab","bc","cd","de")
col2 <- c(1,2,3,4)
df1 <- as.data.frame(cbind(col1,col2))
col1 <- c("ab","ef","fg","gh")
col3 <- c(5,6,7,8)
df2 <- as.data.frame(cbind(col1,col3))
library(plyr)
Example <- join(df1,df2,by = "col1", type = "full") #Does not keep col3
library(dplyr)
Example <- full_join(df1,df2,by = "col1") #Function not recognised

我想要输出...

col1 col2 col3
ab    1    5
bc    2    0
cd    3    0
de    4    0
ef    0    6
fg    0    7
gh    0    8

推荐答案

在上述大卫·阿伦伯格(David Arenberg)发表评论之后...

Following David Arenberg's comment above...

Example <- merge(df1, df2, by = "col1", all = TRUE)

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