假设我有这个数据框:
times vals
1 1 2
2 3 4
3 7 6
设置
foo <- data.frame(times=c(1,3,7), vals=c(2,4,6))
我想要这个:
times vals
1 1 2
2 2 2
3 3 4
4 4 4
5 5 4
6 6 4
7 7 6
也就是说,我要填写从1到7的所有时间,并从不大于给定时间的最近时间开始填写值。
我有一些使用dplyr进行编码的代码,但这很丑陋。建议更好?
library(dplyr)
foo <- merge(foo, data.frame(times=1:max(foo$times)), all.y=TRUE)
foo2 <- merge(foo, foo, by=c(), suffixes=c('', '.1'))
foo2 <- foo2 %>% filter(is.na(vals) & !is.na(vals.1) & times.1 <= times) %>%
group_by(times) %>% arrange(-times.1) %>% mutate(rn = row_number()) %>%
filter(rn == 1) %>%
mutate(vals = vals.1,
rn = NULL,
vals.1 = NULL,
times.1 = NULL)
foo <- merge(foo, foo2, by=c('times'), all.x=TRUE, suffixes=c('', '.2'))
foo <- mutate(foo,
vals = ifelse(is.na(vals), vals.2, vals),
vals.2 = NULL)
最佳答案
dplyr
和tidyr
选项:
library(dplyr)
library(tidyr)
foo %>%
right_join(data_frame(times = min(foo$times):max(foo$times))) %>%
fill(vals)
# Joining by: "times"
# times vals
# 1 1 2
# 2 2 2
# 3 3 4
# 4 4 4
# 5 5 4
# 6 6 4
# 7 7 6
关于r - 在R?的数据框中填写值?,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/37168929/