更新时间:2022-06-25 16:49:52
)错误,则表示其含义。与python不同,R无法解释 1000<值< 5001
。相反,您需要使用 1000<价值和值< 5001
Like many (some) errors, it means what it says. Unlike python, R can't interpret 1000 < value < 5001
. Instead you need to use 1000 < value & value < 5001
library(data.table)
dt <- data.table(value = c(1000, 2500, 5080, 10009))
dt[, Range := ifelse(value < 1001, "0-1000", ifelse(1000 < value & value < 5001, "1001-5000", ifelse(5000 < value & value < 10001, "5001-10000", "10001-20000")))]
dt
value Range
1: 1000 0-1000
2: 2500 1001-5000
3: 5080 5001-10000
4: 10009 10001-20000
正如@akrun提到的那样,您可能会有一个更好的选择。例如:
As @akrun mentioned, you may be better off with a factor. Here's an example:
dt[, Range := cut(value, breaks = c(0, 1001, 5001, 10001, 20001), labels = c("0-1000", "1001-5000", "5001-10000", "10001-20000"))]
这会产生一个显示相同方式的data.table,但是提取 Range
列将为您提供一个与范围。
This produces a data.table that displays the same way, but extracting the Range
column will give you a factor corresponding to the ranges.