[{"data":1,"prerenderedAt":551},["ShallowReactive",2],{"tag-Python":3},[4],{"id":5,"title":6,"body":7,"date":538,"description":539,"draft":540,"extension":541,"meta":542,"navigation":94,"path":543,"seo":544,"stem":545,"summary":546,"tags":547,"__hash__":550},"posts\u002Fposts\u002Funiversity-python-notes.md","开学前的那几页 Python 笔记",{"type":8,"value":9,"toc":532},"minimark",[10,17,21,65,69,72,188,191,425,429,479,488,493,496,528],[11,12,13],"blockquote",{},[14,15,16],"p",{},"这篇是 2019 年 8 月记的，上大学前的那个暑假。原文照抄，只调了排版，当时写错的地方一处都没改。",[18,19,20],"h2",{"id":20},"语法零碎",[22,23,24,28,31,34,40,43,46,49,52,59,62],"ul",{},[25,26,27],"li",{},"（）不可变",[25,29,30],{},"【】可变",[25,32,33],{},"｛｝可变，无序",[25,35,36,37],{},"形式常亮用大写！CONSTANT = ",[38,39],"span",{},[25,41,42],{},"模块变量按规则都应该是常亮，变量放函数或者类里头",[25,44,45],{},"Pycharm好像没有模块常量波浪线标注建议大写功能？",[25,47,48],{},"Range(0,10) 表示1-9",[25,50,51],{},"Print(x,end=’|’)打印完成不换行，以|分隔",[25,53,54,55,58],{},"B = a",[38,56,57],{},"0:len(a):2"," b数组获取a 相当于range(0,len(a),2)",[25,60,61],{},"Break终止循环 contiune跳过这一轮循环",[25,63,64],{},"Len(a) a的字串长度",[18,66,68],{"id":67},"random-模块","random 模块",[14,70,71],{},"用法是从别处抄来的，第一段的作者署名我留在了代码里：",[73,74,79],"pre",{"className":75,"code":76,"language":77,"meta":78,"style":78},"language-python shiki shiki-themes github-light github-dark","#!\u002Fusr\u002Fbin\u002Fpython\n\n## -*- coding: UTF-8 -*-\n\nimport random\n\nprint( random.randint(1,10) )        # 产生 1 到 10 的一个整数型随机数\nprint( random.random() )             # 产生 0 到 1 之间的随机浮点数\nprint( random.uniform(1.1,5.4) )     # 产生  1.1 到 5.4 之间的随机浮点数，区间可以不是整数\nprint( random.choice('tomorrow') )   # 从序列中随机选取一个元素\nprint( random.randrange(1,100,2) )   # 生成从1到100的间隔为2的随机整数\n\na=[1,3,5,6,7]                # 将序列a中的元素顺序打乱\nrandom.shuffle(a)\nprint(a)\n\n# 冷面做的梦\n# 1年前 (2018-05-23)\n","python","",[80,81,82,89,96,102,107,113,118,124,130,136,142,148,153,159,165,171,176,182],"code",{"__ignoreMap":78},[38,83,86],{"class":84,"line":85},"line",1,[38,87,88],{},"#!\u002Fusr\u002Fbin\u002Fpython\n",[38,90,92],{"class":84,"line":91},2,[38,93,95],{"emptyLinePlaceholder":94},true,"\n",[38,97,99],{"class":84,"line":98},3,[38,100,101],{},"## -*- coding: UTF-8 -*-\n",[38,103,105],{"class":84,"line":104},4,[38,106,95],{"emptyLinePlaceholder":94},[38,108,110],{"class":84,"line":109},5,[38,111,112],{},"import random\n",[38,114,116],{"class":84,"line":115},6,[38,117,95],{"emptyLinePlaceholder":94},[38,119,121],{"class":84,"line":120},7,[38,122,123],{},"print( random.randint(1,10) )        # 产生 1 到 10 的一个整数型随机数\n",[38,125,127],{"class":84,"line":126},8,[38,128,129],{},"print( random.random() )             # 产生 0 到 1 之间的随机浮点数\n",[38,131,133],{"class":84,"line":132},9,[38,134,135],{},"print( random.uniform(1.1,5.4) )     # 产生  1.1 到 5.4 之间的随机浮点数，区间可以不是整数\n",[38,137,139],{"class":84,"line":138},10,[38,140,141],{},"print( random.choice('tomorrow') )   # 从序列中随机选取一个元素\n",[38,143,145],{"class":84,"line":144},11,[38,146,147],{},"print( random.randrange(1,100,2) )   # 生成从1到100的间隔为2的随机整数\n",[38,149,151],{"class":84,"line":150},12,[38,152,95],{"emptyLinePlaceholder":94},[38,154,156],{"class":84,"line":155},13,[38,157,158],{},"a=[1,3,5,6,7]                # 将序列a中的元素顺序打乱\n",[38,160,162],{"class":84,"line":161},14,[38,163,164],{},"random.shuffle(a)\n",[38,166,168],{"class":84,"line":167},15,[38,169,170],{},"print(a)\n",[38,172,174],{"class":84,"line":173},16,[38,175,95],{"emptyLinePlaceholder":94},[38,177,179],{"class":84,"line":178},17,[38,180,181],{},"# 冷面做的梦\n",[38,183,185],{"class":84,"line":184},18,[38,186,187],{},"# 1年前 (2018-05-23)\n",[14,189,190],{},"第二段：",[73,192,194],{"className":75,"code":193,"language":77,"meta":78,"style":78},"#!\u002Fusr\u002Fbin\u002Fpython\n\n## -*- coding: UTF-8 -*-\n\nimport random\nimport string\n\n#### 随机整数：\n\nprint random.randint(1,50)\n\n#### 随机选取0到100间的偶数：\n\nprint random.randrange(0, 101, 2)\n\n#### 随机浮点数：\n\nprint random.random()\nprint random.uniform(1, 10)\n\n#### 随机字符：\n\nprint random.choice('abcdefghijklmnopqrstuvwxyz!@#$%^&*()')\n\n#### 多个字符中生成指定数量的随机字符：\n\nprint random.sample('zyxwvutsrqponmlkjihgfedcba',5)\n\n#### 从a-zA-Z0-9生成指定数量的随机字符：\n\nran_str = ''.join(random.sample(string.ascii_letters + string.digits, 8))\nprint ran_str\n\n#### 多个字符中选取指定数量的字符组成新字符串：\n\nprint ''.join(random.sample(['z','y','x','w','v','u','t','s','r','q','p','o','n','m','l','k','j','i','h','g','f','e','d','c','b','a'], 5))\n\n#### 随机选取字符串：\n\nprint random.choice(['剪刀', '石头', '布'])\n\n#### 打乱排序\n\nitems = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0]\nprint random.shuffle(items)\n",[80,195,196,200,204,208,212,216,221,225,230,234,239,243,248,252,257,261,266,270,275,281,286,292,297,303,308,314,319,325,330,336,341,347,353,358,364,369,375,380,386,391,397,402,408,413,419],{"__ignoreMap":78},[38,197,198],{"class":84,"line":85},[38,199,88],{},[38,201,202],{"class":84,"line":91},[38,203,95],{"emptyLinePlaceholder":94},[38,205,206],{"class":84,"line":98},[38,207,101],{},[38,209,210],{"class":84,"line":104},[38,211,95],{"emptyLinePlaceholder":94},[38,213,214],{"class":84,"line":109},[38,215,112],{},[38,217,218],{"class":84,"line":115},[38,219,220],{},"import string\n",[38,222,223],{"class":84,"line":120},[38,224,95],{"emptyLinePlaceholder":94},[38,226,227],{"class":84,"line":126},[38,228,229],{},"#### 随机整数：\n",[38,231,232],{"class":84,"line":132},[38,233,95],{"emptyLinePlaceholder":94},[38,235,236],{"class":84,"line":138},[38,237,238],{},"print random.randint(1,50)\n",[38,240,241],{"class":84,"line":144},[38,242,95],{"emptyLinePlaceholder":94},[38,244,245],{"class":84,"line":150},[38,246,247],{},"#### 随机选取0到100间的偶数：\n",[38,249,250],{"class":84,"line":155},[38,251,95],{"emptyLinePlaceholder":94},[38,253,254],{"class":84,"line":161},[38,255,256],{},"print random.randrange(0, 101, 2)\n",[38,258,259],{"class":84,"line":167},[38,260,95],{"emptyLinePlaceholder":94},[38,262,263],{"class":84,"line":173},[38,264,265],{},"#### 随机浮点数：\n",[38,267,268],{"class":84,"line":178},[38,269,95],{"emptyLinePlaceholder":94},[38,271,272],{"class":84,"line":184},[38,273,274],{},"print random.random()\n",[38,276,278],{"class":84,"line":277},19,[38,279,280],{},"print random.uniform(1, 10)\n",[38,282,284],{"class":84,"line":283},20,[38,285,95],{"emptyLinePlaceholder":94},[38,287,289],{"class":84,"line":288},21,[38,290,291],{},"#### 随机字符：\n",[38,293,295],{"class":84,"line":294},22,[38,296,95],{"emptyLinePlaceholder":94},[38,298,300],{"class":84,"line":299},23,[38,301,302],{},"print random.choice('abcdefghijklmnopqrstuvwxyz!@#$%^&*()')\n",[38,304,306],{"class":84,"line":305},24,[38,307,95],{"emptyLinePlaceholder":94},[38,309,311],{"class":84,"line":310},25,[38,312,313],{},"#### 多个字符中生成指定数量的随机字符：\n",[38,315,317],{"class":84,"line":316},26,[38,318,95],{"emptyLinePlaceholder":94},[38,320,322],{"class":84,"line":321},27,[38,323,324],{},"print random.sample('zyxwvutsrqponmlkjihgfedcba',5)\n",[38,326,328],{"class":84,"line":327},28,[38,329,95],{"emptyLinePlaceholder":94},[38,331,333],{"class":84,"line":332},29,[38,334,335],{},"#### 从a-zA-Z0-9生成指定数量的随机字符：\n",[38,337,339],{"class":84,"line":338},30,[38,340,95],{"emptyLinePlaceholder":94},[38,342,344],{"class":84,"line":343},31,[38,345,346],{},"ran_str = ''.join(random.sample(string.ascii_letters + string.digits, 8))\n",[38,348,350],{"class":84,"line":349},32,[38,351,352],{},"print ran_str\n",[38,354,356],{"class":84,"line":355},33,[38,357,95],{"emptyLinePlaceholder":94},[38,359,361],{"class":84,"line":360},34,[38,362,363],{},"#### 多个字符中选取指定数量的字符组成新字符串：\n",[38,365,367],{"class":84,"line":366},35,[38,368,95],{"emptyLinePlaceholder":94},[38,370,372],{"class":84,"line":371},36,[38,373,374],{},"print ''.join(random.sample(['z','y','x','w','v','u','t','s','r','q','p','o','n','m','l','k','j','i','h','g','f','e','d','c','b','a'], 5))\n",[38,376,378],{"class":84,"line":377},37,[38,379,95],{"emptyLinePlaceholder":94},[38,381,383],{"class":84,"line":382},38,[38,384,385],{},"#### 随机选取字符串：\n",[38,387,389],{"class":84,"line":388},39,[38,390,95],{"emptyLinePlaceholder":94},[38,392,394],{"class":84,"line":393},40,[38,395,396],{},"print random.choice(['剪刀', '石头', '布'])\n",[38,398,400],{"class":84,"line":399},41,[38,401,95],{"emptyLinePlaceholder":94},[38,403,405],{"class":84,"line":404},42,[38,406,407],{},"#### 打乱排序\n",[38,409,411],{"class":84,"line":410},43,[38,412,95],{"emptyLinePlaceholder":94},[38,414,416],{"class":84,"line":415},44,[38,417,418],{},"items = [1, 2, 3, 4, 5, 6, 7, 8, 9, 0]\n",[38,420,422],{"class":84,"line":421},45,[38,423,424],{},"print random.shuffle(items)\n",[18,426,428],{"id":427},"模块导入和别的","模块、导入和别的",[22,430,431,434,437,440,443,446,449,452,455,458,461,464,467,470,473,476],{},[25,432,433],{},".dll是C#里类似模块的 组织结构 动态链接库 .lib静态链接库",[25,435,436],{},".jar也是",[25,438,439],{},"Pack._init_这个写法是错的，_init_直接用pack表达",[25,441,442],{},"Import c7",[25,444,445],{},"Print(c7.a)这样能把c7模块的a打印出来",[25,447,448],{},"解释型语言在意import print顺序",[25,450,451],{},"同级模块不用目录直接名字就好，高级导入次级需要 子报名.模块名",[25,453,454],{},".pyc是编译器做的自检码，提升运行效率，可以被反编译，谨防小偷！",[25,456,457],{},"Round(a,b) a数字b位四舍五入",[25,459,460],{},"Python命令行help()查询函数",[25,462,463],{},"Sys.函数能改很多人工限制",[25,465,466],{},"循环调用最多3923 3925次",[25,468,469],{},"定义立刻执行，声明等着以后执行",[25,471,472],{},"_不推荐外部调用；__防止被继承覆盖",[25,474,475],{},"__dict__是类内变量",[25,477,478],{},"a = list(range(1,5)) list()只接受单个参数，结果：",[73,480,482],{"className":75,"code":481,"language":77,"meta":78,"style":78},"a = [1, 2, 3, 4]\n",[80,483,484],{"__ignoreMap":78},[38,485,486],{"class":84,"line":85},[38,487,481],{},[22,489,490],{},[25,491,492],{},"序列解包不是并行过程",[18,494,495],{"id":495},"现在回头看",[22,497,498,504,518,525],{},[25,499,500,503],{},[80,501,502],{},"range(0, 10)"," 是 0 到 9。我那时候写「表示 1-9」，两头都记错了。",[25,505,506,509,510,513,514,517],{},[80,507,508],{},"_init_"," 少了下划线，是 ",[80,511,512],{},"__init__","；",[80,515,516],{},"pack"," 那句到现在我也没还原出当时想说什么。",[25,519,520,521,524],{},"第二段 random 的代码是 Python 2 的（",[80,522,523],{},"print"," 不带括号），我照着抄下来，没看出来它和第一段的区别。",[25,526,527],{},"「循环调用最多 3923 3925 次」这个数，我至今不知道是从哪儿抄的。",[529,530,531],"style",{},"html .default .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .shiki span {color: var(--shiki-default);background: var(--shiki-default-bg);font-style: var(--shiki-default-font-style);font-weight: var(--shiki-default-font-weight);text-decoration: var(--shiki-default-text-decoration);}html .dark .shiki span {color: var(--shiki-dark);background: var(--shiki-dark-bg);font-style: var(--shiki-dark-font-style);font-weight: var(--shiki-dark-font-weight);text-decoration: var(--shiki-dark-text-decoration);}html.dark .shiki span {color: var(--shiki-dark);background: var(--shiki-dark-bg);font-style: var(--shiki-dark-font-style);font-weight: var(--shiki-dark-font-weight);text-decoration: var(--shiki-dark-text-decoration);}",{"title":78,"searchDepth":98,"depth":98,"links":533},[534,535,536,537],{"id":20,"depth":91,"text":20},{"id":67,"depth":91,"text":68},{"id":427,"depth":91,"text":428},{"id":495,"depth":91,"text":495},"2019-08-15","2019 年 8 月，上大学前的暑假自学 Python 记的几页：列表字典、range 的边界、两段抄来的 random 用法，还有一串当时没弄明白的语法。",false,"md",{},"\u002Fposts\u002Funiversity-python-notes",{"title":6,"description":539},"posts\u002Funiversity-python-notes","大学开学前自学 Python 的原始笔记，写错的、想岔的都原样留着。",[548,549],"Python","大学旧笔记","2RMQgL_P1ZC-Z9iyl7X5mRdzSo_DoqecOWGExN51P_c",1792556025030]