如何设置一个变量来分割和舍入到0位小数？

In Ruby, how can I do:

在Ruby中，我该怎么做：

number_total = records / per_page

where per_page = 100, and records = 1050, and then round up so there are no decimals? So, instead of 10.5 it equals 11?

其中per_page = 100，记录= 1050，然后向上舍入，所以没有小数？那么，而不是10.5，它等于11？

3 个解决方案

#1

Edited following a comment

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number_total = (records / per_page.to_f).ceil

#2

@lulala Another root of all evil: cherry-picking results.

@lulala另一个邪恶的根源：挑选樱桃的结果。

Run your benchmark multiple times. I get the following:

多次运行您的基准测试。我得到以下内容：

       user     system      total        real
   0.120000   0.000000   0.120000 (  0.119281)
   0.120000   0.000000   0.120000 (  0.123431)

Which is a tie.

这是一个平局。

       user     system      total        real
   0.110000   0.000000   0.110000 (  0.118602)
   0.130000   0.000000   0.130000 (  0.127195)

Which suggests that float_op is faster.

这表明float_op更快。

       user     system      total        real
   0.150000   0.000000   0.150000 (  0.151104)
   0.120000   0.000000   0.120000 (  0.123836)

Which suggests that integer_op us faster.

这表明integer_op更快。

#3

Here comes root of all evil: a prematurely optimized method:

这是所有邪恶的根源：过早优化的方法：

class Integer
  # returns quotient's ceiling integer
  def div_ceil(divisor)
    q = self / divisor
    if self % divisor > 0
      return q + 1
    else
      return q
    end
  end
end

The following benchmark code:

以下基准代码：

require 'benchmark'

$a = 1050
$b = 100

def float_op
  ( $a / $b.to_f ).ceil
end

def integer_op
  q = $a / $b
  if $a % $b > 0
    return q + 1
  else
    return q
  end
end

n = 1000000
Benchmark.bm do |x|
  x.report { n.times do; float_op; end }
  x.report { n.times do; integer_op; end }
end

Gives me this result

给我这个结果

       user     system      total        real
   0.160000   0.000000   0.160000 (  0.157589)
   0.130000   0.000000   0.130000 (  0.133821)

#1