r - tidyR 从长到宽的数据？

Question

我有看起来像这样的数据

df = data.frame(name=c("A","A","B","B"),
                group=c("g1","g2","g1","g2"),
                V1=c(10,40,20,30),
                V2=c(6,3,1,7))

我想 reshape 它看起来像这样:

df = data.frame(name=c("A", "B"),               
                V1.g1=c(10,20),
                V1.g2=c(40,30),
                V2.g1=c(6,1),
                V2.g2=c(3,7))

tidyR可以做到吗？

我可以通过 reshape 来做到这一点

reshape(df, idvar='name', timevar='group', direction='wide')

但是学习新东西总是好的。

Answer 1

从 tidyr 1.0.0 开始，您可以执行以下操作:

library(tidyr)

df = data.frame(name=c("A","A","B","B"),
                group=c("g1","g2","g1","g2"),
                V1=c(10,40,20,30),
                V2=c(6,3,1,7))

pivot_wider(df, names_from = "group", values_from = c("V1", "V2"), names_sep = ".")
#> # A tibble: 2 x 5
#>   name  V1.g1 V1.g2 V2.g1 V2.g2
#>   <fct> <dbl> <dbl> <dbl> <dbl>
#> 1 A        10    40     6     3
#> 2 B        20    30     1     7

创建于 2019-09-14 由 reprex package (v0.3.0)