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: 217,049 × 3
##    date       location         n
##    <date>     <chr>        <int>
##  1 2013-07-26 Moree         4500
##  2 2014-11-03 GoldCoast     4531
##  3 2011-10-25 Portland      4500
##  4 2015-04-24 MountGambier  4530
##  5 2020-05-14 Sydney        4835
##  6 2010-03-14 Townsville    4531
##  7 2008-09-29 Canberra      4927
##  8 2011-05-27 AliceSprings  4531
##  9 2020-05-13 Richmond      4500
## 10 2013-10-17 Cairns        4531
## # … with 217,039 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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