purrr

循环（重复）公式

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1 Setup

Package purrr 可以通过载入 tidyverse 使用。

library(tidyverse)

2 A samll example

mpg %>% 
  filter(cyl==4) %>% 
  filter(cty>=quantile(cty,probs = 0.9)) %>% 
  count(manufacturer,model,class)

# A tibble: 4 × 4
  manufacturer model      class          n
  <chr>        <chr>      <chr>      <int>
1 honda        civic      subcompact     4
2 toyota       corolla    compact        3
3 volkswagen   jetta      compact        1
4 volkswagen   new beetle subcompact     2

mpg %>% 
  drop_na() %>% 
  map_lgl(is.numeric)

manufacturer        model        displ         year          cyl        trans 
       FALSE        FALSE         TRUE         TRUE         TRUE        FALSE 
         drv          cty          hwy           fl        class 
       FALSE         TRUE         TRUE        FALSE        FALSE