标签 r
<分区>
我想在现有列的基础上创建一个新列，但是在上面一行
开始于:
df <- data.frame(a=c(1:10), b=c("red", "yellow", "blue", "green", "yellow", "purple", "blue", "green", "yellow", "purple"))
结果如下:
df <- data.frame(a=c(1:10), b=c("red", "yellow", "blue", "green", "yellow", "purple", "blue", "green", "yellow", "purple"), c=c("na", "red", "yellow", "blue", "green", "yellow", "purple", "blue", "green", "yellow"))
感谢您提供的任何帮助
最佳答案
使用 data.table 包中的 shift 的一种方法:
library(data.table)
df$c <- shift(df$b, 1)
df
# a b c
#1 1 red <NA>
#2 2 yellow red
#3 3 blue yellow
#4 4 green blue
#5 5 yellow green
#6 6 purple yellow
#7 7 blue purple
#8 8 green blue
#9 9 yellow green
#10 10 purple yellow
关于r - 在现有列的基础上创建一个新列，但在上面的行，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/46846803/