实训报告

## -- Attaching packages --------------------------------------- tidyverse 1.3.1 --

## v ggplot2 3.3.5     v purrr   0.3.4
## v tibble  3.1.6     v dplyr   1.0.8
## v tidyr   1.2.0     v stringr 1.4.0
## v readr   2.1.2     v forcats 0.5.1

## -- Conflicts ------------------------------------------ tidyverse_conflicts() --
## x dplyr::filter() masks stats::filter()
## x dplyr::lag()    masks stats::lag()

## Warning: 程辑包'modelr'是用R版本4.1.3 来建造的

## Warning: 程辑包'nycflights13'是用R版本4.1.3 来建造的

## 
## 载入程辑包：'lubridate'

## The following objects are masked from 'package:base':
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##     date, intersect, setdiff, union