我想用 ifelse() 条件创建几个列。这是我的示例代码:
df <- tibble(
date = lubridate::today() +0:9,
return= c(1,2.5,2,3,5,6.5,1,9,3,2))
现在我想添加具有升序条件的新列(从 1 到 8)。第一列应该只包含来自“return”列的大于 1 的值,第二列应该只包含大于 2 的值,依此类推...我可以使用 mutate() 函数计算每一列:
df <- df %>% mutate( `return>1`= ifelse(return > 1, return, NA))
df <- df %>% mutate( `return>2`= ifelse(return > 2, return, NA))
df <- df %>% mutate( `return>3`= ifelse(return > 3, return, NA))
df <- df %>% mutate( `return>4`= ifelse(return > 4, return, NA))
df <- df %>% mutate( `return>5`= ifelse(return > 5, return, NA))
df <- df %>% mutate( `return>6`= ifelse(return > 6, return, NA))
df <- df %>% mutate( `return>7`= ifelse(return > 7, return, NA))
df <- df %>% mutate( `return>8`= ifelse(return > 8, return, NA))
> head(df)
# A tibble: 6 x 10
date return `return>1` `return>2` `return>3` `return>4` `return>5` `return>6` `return>7` `return>8`
<date> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
1 2019-03-08 1 NA NA NA NA NA NA NA NA
2 2019-03-09 2.5 2.5 2.5 NA NA NA NA NA NA
3 2019-03-10 2 2 NA NA NA NA NA NA NA
4 2019-03-11 3 3 3 NA NA NA NA NA NA
5 2019-03-12 5 5 5 5 5 NA NA NA NA
6 2019-03-13 6.5 6.5 6.5 6.5 6.5 6.5 6.5 NA NA
有没有更简单的方法来创建所有这些列并减少所有这些代码?也许使用 map_function?有没有办法自动命名新列?
最佳答案
带有 lapply
的选项
n <- seq(1, 8)
df[paste0("return > ", n)] <- lapply(n, function(x)
replace(df$return, df$return <= x, NA))
# date return `return > 1` `return > 2` `return > 3` .....
# <date> <dbl> <dbl> <dbl> <dbl>
#1 2019-03-08 1 NA NA NA
#2 2019-03-09 2.5 2.5 2.5 NA
#3 2019-03-10 2 2 NA NA
#4 2019-03-11 3 3 3 NA
#5 2019-03-12 5 5 5 5
#6 2019-03-13 6.5 6.5 6.5 6.5
#...
关于R 使用 ifelse() 条件改变多列,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/55059761/