晋太元中，武陵人捕鱼为业。缘溪行，忘路之远近。忽逢桃花林，夹岸数百步，中无杂树，芳草鲜美，落英缤纷。渔人甚异之，复前行，欲穷其林。 　　林尽水源，便得一山，山有小口，仿佛若有光。便舍船，从口入。初极狭，才通人。复行数十步，豁然开朗。土地平旷，屋舍俨然，有良田、美池、桑竹之属。阡陌交通，鸡犬相闻。其中往来种作，男女衣着，悉如外人。黄发垂髫，并怡然自乐。 　　见渔人，乃大惊，问所从来。具答之。便要还家，设酒杀鸡作食。村中闻有此人，咸来问讯。自云先世避秦时乱，率妻子邑人来此绝境，不复出焉，遂与外人间隔。问今是何世，乃不知有汉，无论魏晋。此人一一为具言所闻，皆叹惋。余人各复延至其家，皆出酒食。停数日，辞去。此中人语云：“不足为外人道也。”(间隔 一作：隔绝) 　　既出，得其船，便扶向路，处处志之。及郡下，诣太守，说如此。太守即遣人随其往，寻向所志，遂迷，不复得路。 　　南阳刘子骥，高尚士也，闻之，欣然规往。未果，寻病终。后遂无问津者。 sh-3ll

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--- !ruby/object:RI::ClassDescription 
attributes: []

class_methods: []

comment: 
- !ruby/struct:SM::Flow::P 
  body: The Benchmark module provides methods to measure and report the time used to execute Ruby code.
- !ruby/object:SM::Flow::LIST 
  contents: 
  - !ruby/struct:SM::Flow::LI 
    label: "*"
    body: "Measure the time to construct the string given by the expression <tt>&quot;a&quot;*1_000_000</tt>:"
  - !ruby/struct:SM::Flow::VERB 
    body: "    require 'benchmark'\n\n    puts Benchmark.measure { &quot;a&quot;*1_000_000 }\n"
  - !ruby/struct:SM::Flow::P 
    body: "On my machine (FreeBSD 3.2 on P5, 100MHz) this generates:"
  - !ruby/struct:SM::Flow::VERB 
    body: "    1.166667   0.050000   1.216667 (  0.571355)\n"
  - !ruby/struct:SM::Flow::P 
    body: This report shows the user CPU time, system CPU time, the sum of the user and system CPU times, and the elapsed real time. The unit of time is seconds.
  - !ruby/struct:SM::Flow::LI 
    label: "*"
    body: "Do some experiments sequentially using the #bm method:"
  - !ruby/struct:SM::Flow::VERB 
    body: "    require 'benchmark'\n\n    n = 50000\n    Benchmark.bm do |x|\n      x.report { for i in 1..n; a = &quot;1&quot;; end }\n      x.report { n.times do   ; a = &quot;1&quot;; end }\n      x.report { 1.upto(n) do ; a = &quot;1&quot;; end }\n    end\n"
  - !ruby/struct:SM::Flow::P 
    body: "The result:"
  - !ruby/struct:SM::Flow::VERB 
    body: "           user     system      total        real\n       1.033333   0.016667   1.016667 (  0.492106)\n       1.483333   0.000000   1.483333 (  0.694605)\n       1.516667   0.000000   1.516667 (  0.711077)\n"
  - !ruby/struct:SM::Flow::LI 
    label: "*"
    body: "Continuing the previous example, put a label in each report:"
  - !ruby/struct:SM::Flow::VERB 
    body: "    require 'benchmark'\n\n    n = 50000\n    Benchmark.bm(7) do |x|\n      x.report(&quot;for:&quot;)   { for i in 1..n; a = &quot;1&quot;; end }\n      x.report(&quot;times:&quot;) { n.times do   ; a = &quot;1&quot;; end }\n      x.report(&quot;upto:&quot;)  { 1.upto(n) do ; a = &quot;1&quot;; end }\n    end\n"
  type: :BULLET
- !ruby/struct:SM::Flow::P 
  body: "The result:"
- !ruby/struct:SM::Flow::VERB 
  body: "                    user     system      total        real\n       for:     1.050000   0.000000   1.050000 (  0.503462)\n       times:   1.533333   0.016667   1.550000 (  0.735473)\n       upto:    1.500000   0.016667   1.516667 (  0.711239)\n"
- !ruby/object:SM::Flow::LIST 
  contents: 
  - !ruby/struct:SM::Flow::LI 
    label: "*"
    body: "The times for some benchmarks depend on the order in which items are run. These differences are due to the cost of memory allocation and garbage collection. To avoid these discrepancies, the #bmbm method is provided. For example, to compare ways to sort an array of floats:"
  - !ruby/struct:SM::Flow::VERB 
    body: "    require 'benchmark'\n\n    array = (1..1000000).map { rand }\n\n    Benchmark.bmbm do |x|\n      x.report(&quot;sort!&quot;) { array.dup.sort! }\n      x.report(&quot;sort&quot;)  { array.dup.sort  }\n    end\n"
  - !ruby/struct:SM::Flow::P 
    body: "The result:"
  - !ruby/struct:SM::Flow::VERB 
    body: "     Rehearsal -----------------------------------------\n     sort!  11.928000   0.010000  11.938000 ( 12.756000)\n     sort   13.048000   0.020000  13.068000 ( 13.857000)\n     ------------------------------- total: 25.006000sec\n\n                 user     system      total        real\n     sort!  12.959000   0.010000  12.969000 ( 13.793000)\n     sort   12.007000   0.000000  12.007000 ( 12.791000)\n"
  - !ruby/struct:SM::Flow::LI 
    label: "*"
    body: "Report statistics of sequential experiments with unique labels, using the #benchmark method:"
  - !ruby/struct:SM::Flow::VERB 
    body: "    require 'benchmark'\n\n    n = 50000\n    Benchmark.benchmark(&quot; &quot;*7 + CAPTION, 7, FMTSTR, &quot;&gt;total:&quot;, &quot;&gt;avg:&quot;) do |x|\n      tf = x.report(&quot;for:&quot;)   { for i in 1..n; a = &quot;1&quot;; end }\n      tt = x.report(&quot;times:&quot;) { n.times do   ; a = &quot;1&quot;; end }\n      tu = x.report(&quot;upto:&quot;)  { 1.upto(n) do ; a = &quot;1&quot;; end }\n      [tf+tt+tu, (tf+tt+tu)/3]\n    end\n"
  - !ruby/struct:SM::Flow::P 
    body: "The result:"
  - !ruby/struct:SM::Flow::VERB 
    body: "                  user     system      total        real\n     for:     1.016667   0.016667   1.033333 (  0.485749)\n     times:   1.450000   0.016667   1.466667 (  0.681367)\n     upto:    1.533333   0.000000   1.533333 (  0.722166)\n     &gt;total:  4.000000   0.033333   4.033333 (  1.889282)\n     &gt;avg:    1.333333   0.011111   1.344444 (  0.629761)\n"
  type: :BULLET
constants: 
- !ruby/object:RI::Constant 
  comment: 
  name: BENCHMARK_VERSION
  value: "\"2002-04-25\""
- !ruby/object:RI::Constant 
  comment: 
  - !ruby/struct:SM::Flow::P 
    body: The default caption string (heading above the output times).
  name: CAPTION
  value: Benchmark::Tms::CAPTION
- !ruby/object:RI::Constant 
  comment: 
  - !ruby/struct:SM::Flow::P 
    body: The default format string used to display times. See also Benchmark::Tms#format.
  name: FMTSTR
  value: Benchmark::Tms::FMTSTR
full_name: Benchmark
includes: []

instance_methods: 
- !ruby/object:RI::MethodSummary 
  name: benchmark
- !ruby/object:RI::MethodSummary 
  name: bm
- !ruby/object:RI::MethodSummary 
  name: bmbm
- !ruby/object:RI::MethodSummary 
  name: measure
- !ruby/object:RI::MethodSummary 
  name: realtime
name: Benchmark
superclass: