摘要数据框架

Question

我有以下数据库。 如何忽略空单元格并压缩成一行？

M = data.frame( Name = c('name','name'), Col1 = c("",1) , Col2 = c(2,""))
M$Col1 <- as.character(M$Col1)
M$Col2 <- as.character(M$Col2)

谢谢

Answer 1

As @Nicola already expressed in the comments:

M2 <- aggregate(.~Name, M, paste, collapse="")

is giving the desired output:

> M2
  Name Col1 Col2
1 name    1    2

Answer 2

您可以使用聚合功能来解决您的问题。

aggregate(M[c("Col1","Col2")], list(M$Name), max, na.rm = TRUE)

Answer 3

这是dplyr解决方案

library(dplyr)
M %>%
    group_by(Name) %>%
    summarise(Col1 = paste0(Col1, collapse = ''),
              Col2 = paste0(Col2, collapse = ''))

##     Name  Col1  Col2
##   (fctr) (chr) (chr)
## 1   name     1     2

这基于输入数据而不必将列转换为字符

M = data.frame( Name = c('name','name'), Col1 = c("",1) , Col2 = c(2,""))