与dplyr一起使用base-R`rep()`时遇到问题

时间:2018-10-31 15:21:40

标签: r dplyr

library(tidyverse)
x <- c(0, 20, 30, 58)
n <- 100
df <- data_frame(x, n) %>% 
  distinct() %>%
  filter(x >= 0 & x < n) %>%
  arrange(x) %>%
  bind_rows(data_frame(x = n)) %>%
  mutate(lag_x = lag(x)) %>%
  mutate(y = x - lag_x) %>%
  filter(!is.na(y))

rep(seq_along(df$x), df$y)

上面的代码工作正常。当我尝试使最后一步进入所有中断时。我的语法有什么问题?我希望一切都成为长管。我认为这是不可能的,因为我需要将整个管道(上面的代码块)嵌套在rep()调用中?正确吗?

library(tidyverse)
x <- c(0, 20, 30, 58)
n <- 100
df <- data_frame(x, n) %>% 
  distinct() %>%
  filter(x >= 0 & x < n) %>%
  arrange(x) %>%
  bind_rows(data_frame(x = n)) %>%
  mutate(lag_x = lag(x)) %>%
  mutate(y = x - lag_x) %>%
  filter(!is.na(y)) %>% 
  rep(seq_along(x), y) %>% 
  print()
  

function_list [i]中的错误:未找到对象'y'

1 个答案:

答案 0 :(得分:5)

由于它不在mutate/summarise函数之外,因此我们需要pull或将其提取

data_frame(x, n) %>% 
  distinct() %>%
  filter(x >= 0 & x < n) %>%
  arrange(x) %>%
  bind_rows(data_frame(x = n)) %>%
  mutate(lag_x = lag(x)) %>%
  mutate(y = x - lag_x) %>%
  filter(!is.na(y)) %>% 
  {rep(seq_along(.$x), .$y)}

或者也可以写为

data_frame(x, n) %>% 
 distinct() %>%
 filter(x >= 0 & x < n) %>%
 arrange(x) %>%
 bind_rows(data_frame(x = n)) %>%
 mutate(lag_x = lag(x)) %>%
 mutate(y = x - lag_x) %>%
 filter(!is.na(y)) %>% 
 summarise(n = list(rep(row_number(), y))) %>%
 pull(n)