Count the frequency of 10M integers

10M_ints_count.go

package main
 
import "fmt"
import "math/rand"
import "time"

func main(){
    const n = 10000000
    var arr [n]int
    var counter [100]int

    for i := 0; i < n; i++ {
    	arr[i] = rand.Intn(100)
    }

    for i := 0; i < 100; i++ {
    	counter[i] = 0
    }

    t1 := time.Now()

    for i := 0; i < n; i++ {
    	counter[arr[i]] += 1
    }

    elapsed := time.Since(t1)
    fmt.Println("elapsed: ", elapsed)

    fmt.Println(counter)
}

10M_ints_count.py

import numpy as np
import time
import sys
import random

def time_it(func):
    def clock(*args):
        t0 = time.time()
        result = func(*args)
        elapsed = time.time() - t0
        output = '%s Total time: %0.8f sec' % (func.__name__, elapsed)
        print(output)
        return result
    return clock

@time_it
def np_int_counter(arr):
    data = {}
    for i in range(0, 100):
        data[i] = np.where(arr == i, 1, 0).sum()
    return data

@time_it
def counter_sort_array(arr):
    counter = [0] * 100
    for i in arr:
        counter[i] += 1
    return counter

@time_it
def counter_sort_array_v2(arr):
    counter = [0] * 100
    try:
        while True:
            counter[arr.pop()] += 1
    except IndexError:
        pass
    
    return counter

@time_it
def counter_sort_dict(arr):
    counter = {i: 0 for i in range(0, 100)}
    for i in arr:
        counter[i] += 1
    return counter


arr = [random.randrange(0, 100) for _ in range(10000000)]

print(sys.getsizeof(arr))
counter_sort_array(arr)
counter_sort_dict(arr)
counter_sort_array_v2(arr)

arr = (random.randrange(0, 100) for _ in range(10000000))

print(sys.getsizeof(arr))
counter_sort_array(arr)

arr = (random.randrange(0, 100) for _ in range(10000000))
counter_sort_dict(arr)

arr = np.random.randint(0, 100, size=10000000)
counter_sort_array(arr)
counter_sort_dict(arr)
np_int_counter(arr)

10M_ints_count.rb

require "benchmark"

arr = (0..10000000).map { rand(100) }

array_count = Benchmark.measure do
  count = [0] * 100
  arr.each { |i| count[i] += 1 }
  count
end

hash_count = Benchmark.measure do
  count = (0..100).map { |i| [i, 0] }.to_h
  arr.each { |i| count[i] += 1 }
  count
end

puts array_count
puts hash_count

OutPut of Python

81528048
counter_sort_array Total time: 0.84883595 sec
counter_sort_dict Total time: 0.96123505 sec
counter_sort_array_v2 Total time: 1.25566697 sec
112
counter_sort_array Total time: 9.33644700 sec
counter_sort_dict Total time: 9.52690411 sec
counter_sort_array Total time: 1.87163377 sec
counter_sort_dict Total time: 5.77484274 sec
np_int_counter Total time: 3.52460122 sec

Output of Ruby

  0.557419   0.000614   0.558033 (  0.559095)
  0.843364   0.000670   0.844034 (  0.845160)

Output of Go

elapsed:  10.290499ms