R-将所有4位字符更改为前面有0，但保持所有5位值不变

Question

我正在试着在一个县的层面上制作一张全息地图。每个县都有一个唯一的id。我需要将数据集中的ID合并为该县地理信息的ID。数据集的county_id为4位数字，例如1001。地理数据在ID 01001中。所有5位数的county_ids都是正确的。

下面是我的解决方案，但我假设有更好的方法来做到这一点。请教我一种更有效率的方法。

library(tidyverse)
library(urbnmapr)
library(janitor)

broadband <- readr::read_csv('https://raw.githubusercontent.com/rfordatascience/tidytuesday/master/data/2021/2021-05-11/broadband.csv') %>% 
  clean_names()

  broadband_4_digits <- broadband %>% 
  mutate(id_length = str_length(county_id)) %>% 
  filter(id_length == 4) %>% 
  mutate(county_fips = paste0("0",county_id))

broadband_5_digits <- broadband %>% 
  mutate(id_length = str_length(county_id)) %>% 
  filter(id_length == 5) %>% 
  mutate(county_fips = county_id)

broadband <- rbind(broadband_4_digits, broadband_5_digits)

broadband <- broadband %>% 
  right_join(counties, by = "county_fips")

Answer 1

我们可以通过一个对sub的调用来处理这个问题

broadband$county_id <- sub("^\\d{4}$", paste0("0", broadbad$county_id), broadbad$county_id)

或者我们可以只使用sprintf

broadband$county_id <- sprintf("%05d", broadband$county_id)

Answer 2

您可以使用stringr库中的str_pad函数：

library(stringr)
str_pad(as.character(c(1001,10001)), pad = "0",width = 5)

1 "01001“"10001"