Expressiveness Benchmark

def continent_by_population(countries):
  continent_stats = defaultdict(lambda: [0, 0])
  for country in countries:
    continent = country['continent']
    continent_stats[continent][0] += country['population']
    continent_stats[continent][1] += 1
     
  max_continent = None
  max_average = None
  for continent, [total, count] in continent_stats.items():
    average = total / count
    if max_average is None or max_average < average:
      max_average = average
      max_continent = continent
      
  return max_continent

def continent_by_population(countries):
  continents = set([c['continent'] for c in countries])
  populations_by_continent = [
    (continent, [c['population'] for c in countries 
                 if c['continent'] == continent])
    for continent in continents
  ]
  averages = [
    (continent, sum(pops) / len(pops))
    for continent, pops in populations_by_continent
  ]
  return max(averages, key=lambda t: t[1])[0]

def continent_by_population(countries):
  mean_pop = countries.groupby('continent').population.mean()
  return mean_pop.index[mean_pop.argmax()]

continent_by_population <- function(countries) {
  countries %>%
    group_by(continent) %>%
    summarize(mean_pop = mean(population)) %>%
    slice(which.max(mean_pop)) %>%
    .$continent
}

SELECT continent 
FROM countries
GROUP BY continent
ORDER BY AVG(population) DESC
LIMIT 1

.decl average_population(Continent:symbol, Avg:number)
average_population(Continent, Avg) :-
  countries(Continent, _, _),
  Total = sum P : countries(Continent, _, P),
  Num_countries = count : countries(Continent, _, _),
  Avg = Total / Num_countries.
  
continent_by_population(Continent) :- 
  countries(Continent, _, _), 
  average_population(Continent, Max_avg),
  Max_avg = max A : { countries(C, _, _), average_population(C, A) }.

averages: 
  select avg(population) by continent from countries;
continent_by_population: 
  (first select[>population] continent from averages) `continent