10.5 Add Counts

20200814 Using dplyr::add_count() a new column will be added to the dataset recording the size of groups. The column name will be n.

ds %<>%
  add_count(location) %T>%
  {
    select(., date, location, n) %>%
    sample_frac() %>%
    print()
  }

## # A tibble: 275,410 × 3
##    date       location          n
##    <date>     <chr>         <int>
##  1 2015-04-17 SydneyAirport  5751
##  2 2014-07-07 Launceston     5782
##  3 2024-09-27 NorfolkIsland  5751
##  4 2018-01-07 Nhil           4320
##  5 2023-07-29 NorahHead      5746
##  6 2011-01-15 AliceSprings   5782
##  7 2013-12-08 Witchcliffe    5625
##  8 2011-06-04 Newcastle      4030
##  9 2025-06-06 Cairns         5782
## 10 2017-06-02 Albany         5781
## # ℹ 275,400 more rows

names(ds)

##  [1] "date"            "location"        "min_temp"        "max_temp"       
##  [5] "rainfall"        "evaporation"     "sunshine"        "wind_gust_dir"  
##  [9] "wind_gust_speed" "wind_dir_9am"    "wind_dir_3pm"    "wind_speed_9am" 
## [13] "wind_speed_3pm"  "humidity_9am"    "humidity_3pm"    "pressure_9am"   
## [17] "pressure_3pm"    "cloud_9am"       "cloud_3pm"       "temp_9am"       
## [21] "temp_3pm"        "rain_today"      "risk_mm"         "rain_tomorrow"  
## [25] "n"

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