R 使用基于ID变量的因子值填充缺少的值
我想根据R 使用基于ID变量的因子值填充缺少的值,r,missing-data,R,Missing Data,我想根据ID变量,用正确的因子值填充 以下是变量: ID <- c(1,1,1,2,2,2,3,3,3) Gender_NA <- c("m",NA,"m",NA,"f",NA,"m","m",NA) Gender <- c("m","m","m","f","f","f","m","m","m") ID来自library(zoo)的na.locf函数可用于将na元素替换为相邻的非na先前元素。使用data.table,我们将“data.frame”转换为“data.tabl
ID
变量,用正确的因子值填充
以下是变量:
ID <- c(1,1,1,2,2,2,3,3,3)
Gender_NA <- c("m",NA,"m",NA,"f",NA,"m","m",NA)
Gender <- c("m","m","m","f","f","f","m","m","m")
ID来自library(zoo)
的na.locf
函数可用于将na
元素替换为相邻的非na先前元素。使用data.table
,我们将“data.frame”转换为“data.table”,按“ID”分组,我们用前面的非NA替换NA元素,如果第一个元素是NA,它将不会被替换,我们可以使用第二个NA.locf
选项fromLast=TRUE
将剩余的NA替换为后续的非NA元素
library(zoo)
library(data.table)
setDT(Data_have)[, Gender := na.locf(na.locf(Gender_NA,
na.rm=FALSE),fromLast=TRUE), by = ID][, Gender_NA := NULL]
Data_have
# ID Gender
#1: 1 m
#2: 1 m
#3: 1 m
#4: 2 f
#5: 2 f
#6: 2 f
#7: 3 m
#8: 3 m
#9: 3 m
或者,在按ID
分组时,我们可以使用na.omit()
忽略所有NAs,并按如下方式选择第一个元素:
setDT(Data_have)[, Gender := na.omit(Gender_NA)[1L], by = ID][, Gender_NA := NULL]
或者使用与dplyr相同的方法:
library(dplyr)
Data_have %>%
group_by(ID) %>%
transmute(Gender= first(na.omit(Gender_NA)))
# ID Gender
# (dbl) (fctr)
#1 1 m
#2 1 m
#3 1 m
#4 2 f
#5 2 f
#6 2 f
#7 3 m
#8 3 m
#9 3 m
下面是我如何使用数据。表:
require(data.table) # v1.9.6+
dt = data.table(ID, Gender_NA)
# Gender_NA is of character type
答案如下:
dt[is.na(Gender_NA), Gender_NA := na.omit(dt)[.SD, Gender_NA, mult="first", on="ID"]]
require(data.table) # v1.9.6+
dt = data.table(ID, Gender_NA)
# Gender_NA is of character type
dt[is.na(Gender_NA), Gender_NA := na.omit(dt)[.SD, Gender_NA, mult="first", on="ID"]]