Ruby中，如何比较不同方法的执行效率？

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要确定哪种方法运行得更快，可以比较几种不同的方法来实现`count_between`函数。以下是一个Ruby示例，使用内置的`select`方法，它通常比手动迭代数组更快：

rubydef count_between(list_of_integers, lower_bound, upper_bound) count=list_of_integers.count { |x| lower_bound <=x && x <=upper_bound }end

如何确定哪种方法运行得更快？很难在 Ruby文档中阅读Benchmark并实际实现它.谢谢

def count_between(list_of_integers, lower_bound, upper_bound) count = 0 list_of_integers.each do |x| (x >= lower_bound && x <= upper_bound) ? count += 1 : next end count end

要么

def count_between(list_of_integers, lower_bound, upper_bound) count = 0 list_of_integers.each do |x| count += 1 if x.between?(lower_bound, upper_bound) end count end

require 'benchmark' def count_between_1(list_of_integers, lower_bound, upper_bound) count = 0 list_of_integers.each do |x| (x >= lower_bound && x <= upper_bound) ? count += 1 : next end count end def count_between_2(list_of_integers, lower_bound, upper_bound) count = 0 list_of_integers.each do |x| count += 1 if x.between?(lower_bound, upper_bound) end count end list_of_integers = (1..100_000).to_a lower_bound = 5 upper_bound = 80_000 Benchmark.bm do |x| x.report do count_between_1(list_of_integers, lower_bound, upper_bound) end x.report do count_between_2(list_of_integers, lower_bound, upper_bound) end end

结果如下：

user system total real 0.010000 0.000000 0.010000 ( 0.008910) 0.010000 0.000000 0.010000 ( 0.018098)

所以第一个变种要快得多.