{"id":3630,"date":"2022-03-18T11:43:16","date_gmt":"2022-03-18T03:43:16","guid":{"rendered":"https:\/\/egonlin.com\/?p=3630"},"modified":"2022-03-18T11:43:16","modified_gmt":"2022-03-18T03:43:16","slug":"%e7%ac%ac%e4%b8%80%e8%8a%82%ef%bc%9apandas","status":"publish","type":"post","link":"https:\/\/egonlin.com\/?p=3630","title":{"rendered":"\u7b2c\u4e00\u8282\uff1aPandas"},"content":{"rendered":"<h1>Pandas<\/h1>\n<ul>\n<li>\u4ec0\u4e48\u662fPandas<\/li>\n<li>pandas\u80fd\u5e72\u4ec0\u4e48<\/li>\n<li>\u600e\u4e48\u7528pandas\n<ul>\n<li>Series<\/li>\n<li>DataFrame<\/li>\n<li>\u65f6\u95f4\u5bf9\u8c61\u5904\u7406<\/li>\n<li>\u6570\u636e\u5206\u7ec4\u548c\u805a\u5408<\/li>\n<li>\u5176\u4ed6\u5e38\u7528\u65b9\u6cd5<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h2>1\u3001\u4ec0\u4e48\u662fPandas<\/h2>\n<p>\u200b   \u5f53\u5927\u5bb6\u8c08\u8bba\u5230\u6570\u636e\u5206\u6790\u65f6\uff0c\u63d0\u53ca\u6700\u591a\u7684\u8bed\u8a00\u5c31\u662fPython\u548cSQL\uff0c\u800cPython\u4e4b\u6240\u4ee5\u9002\u5408\u505a\u6570\u636e\u5206\u6790\uff0c\u5c31\u662f\u56e0\u4e3a\u4ed6\u6709\u5f88\u591a\u5f3a\u5927\u7684\u7b2c\u4e09\u65b9\u5e93\u6765\u534f\u52a9\uff0cpandas\u5c31\u662f\u5176\u4e2d\u4e4b\u4e00\uff0c\u5b83\u662f\u57fa\u4e8eNumpy\u6784\u5efa\u7684\uff0c\u6b63\u56e0pandas\u7684\u51fa\u73b0\uff0c\u8ba9Python\u8bed\u8a00\u4e5f\u6210\u4e3a\u4f7f\u7528\u6700\u5e7f\u6cdb\u800c\u4e14\u5f3a\u5927\u7684\u6570\u636e\u5206\u6790\u73af\u5883\u4e4b\u4e00\u3002\u5982\u679c\u8bf4\u6ca1\u6709pandas\u7684\u51fa\u73b0\uff0c\u76ee\u524d\u7684\u91d1\u878d\u6570\u636e\u5206\u6790\u9886\u57df\u8fd8\u5e94\u8be5\u662fR\u8bed\u8a00\u7684\u5929\u4e0b\u3002<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_1.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_1.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h2>2\u3001Pandas\u80fd\u5e72\u4ec0\u4e48<\/h2>\n<p>Pandas\u7684\u4e3b\u8981\u529f\u80fd\uff1a<\/p>\n<ul>\n<li>\u5177\u5907\u5bf9\u5e94\u5176\u529f\u80fd\u7684\u6570\u636e\u7ed3\u6784DataFrame\uff0cSeries<\/li>\n<li>\u96c6\u6210\u65f6\u95f4\u5e8f\u5217\u529f\u80fd<\/li>\n<li>\u63d0\u4f9b\u4e30\u5bcc\u7684\u6570\u5b66\u8fd0\u7b97\u548c\u64cd\u4f5c<\/li>\n<li>\u7075\u6d3b\u5904\u7406\u7f3a\u5931\u6570\u636e<\/li>\n<li>&#8230;..<\/li>\n<\/ul>\n<p>\u4ee5\u4e0a\u5c31\u662fpandas\u80fd\u5b8c\u6210\u7684\u4e00\u4e9b\u57fa\u7840\u64cd\u4f5c\uff0c\u5f53\u7136\u5e76\u4e0d\u5b8c\u5168\uff0c\u4e0b\u9762\u5c31\u6765\u770b\u770bpandas\u5230\u5e95\u662f\u600e\u4e48\u7528\u7684\u3002<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_2.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_2.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h2>3\u3001\u600e\u4e48\u7528Pandas<\/h2>\n<p>\u5b89\u88c5\u65b9\u6cd5\uff1a<\/p>\n<blockquote>\n<p>pip install pandas<\/p>\n<\/blockquote>\n<p>\u5f15\u7528\u65b9\u6cd5\uff1a<\/p>\n<blockquote>\n<p>import pandas as pd<\/p>\n<\/blockquote>\n<h3>3.1\u3001Series<\/h3>\n<p>Series\u662f\u4e00\u79cd\u7c7b\u4f3c\u4e8e\u4e00\u7ef4\u6570\u7ec4\u7684\u5bf9\u8c61\uff0c\u7531\u4e00\u7ec4\u6570\u636e\u548c\u4e00\u7ec4\u4e0e\u4e4b\u76f8\u5173\u7684\u6570\u636e\u6807\u7b7e(\u7d22\u5f15)\u7ec4\u6210\u3002\u5728\u6570\u636e\u5206\u6790\u7684\u8fc7\u7a0b\u4e2d\u975e\u5e38\u5e38\u7528\u3002<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_3.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_3.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.1.1\u3001\u521b\u5efa\u65b9\u6cd5<\/h4>\n<pre><code class=\"language-python\">\u7b2c\u4e00\u79cd\uff1a\npd.Series([4,5,6,7,8])\n\u6267\u884c\u7ed3\u679c\uff1a\n0    4\n1    5\n2    6\n3    7\n4    8\ndtype: int64\n# \u5c06\u6570\u7ec4\u7d22\u5f15\u4ee5\u53ca\u6570\u7ec4\u7684\u503c\u6253\u5370\u51fa\u6765\uff0c\u7d22\u5f15\u5728\u5de6\uff0c\u503c\u5728\u53f3\uff0c\u7531\u4e8e\u6ca1\u6709\u4e3a\u6570\u636e\u6307\u5b9a\u7d22\u5f15\uff0c\u4e8e\u662f\u4f1a\u81ea\u52a8\u521b\u5efa\u4e00\u4e2a0\u5230N-1\uff08N\u4e3a\u6570\u636e\u7684\u957f\u5ea6\uff09\u7684\u6574\u6570\u578b\u7d22\u5f15\uff0c\u53d6\u503c\u7684\u65f6\u5019\u53ef\u4ee5\u901a\u8fc7\u7d22\u5f15\u53d6\u503c\uff0c\u8ddf\u4e4b\u524d\u5b66\u8fc7\u7684\u6570\u7ec4\u548c\u5217\u8868\u4e00\u6837\n-----------------------------------------------\n\u7b2c\u4e8c\u79cd\uff1a\npd.Series([4,5,6,7,8],index=[&#039;a&#039;,&#039;b&#039;,&#039;c&#039;,&#039;d&#039;,&#039;e&#039;])\n\u6267\u884c\u7ed3\u679c\uff1a\na    4\nb    5\nc    6\nd    7\ne    8\ndtype: int64\n# \u81ea\u5b9a\u4e49\u7d22\u5f15\uff0cindex\u662f\u4e00\u4e2a\u7d22\u5f15\u5217\u8868\uff0c\u91cc\u9762\u5305\u542b\u7684\u662f\u5b57\u7b26\u4e32\uff0c\u4f9d\u7136\u53ef\u4ee5\u901a\u8fc7\u9ed8\u8ba4\u7d22\u5f15\u53d6\u503c\u3002\n-----------------------------------------------\n\u7b2c\u4e09\u79cd\uff1a\npd.Series({&quot;a&quot;:1,&quot;b&quot;:2})\n\u6267\u884c\u7ed3\u679c\uff1a\na    1\nb    2\ndtype: int64\n# \u6307\u5b9a\u7d22\u5f15\n-----------------------------------------------\n\u7b2c\u56db\u79cd\uff1a\npd.Series(0,index=[&#039;a&#039;,&#039;b&#039;,&#039;c&#039;])\n\u6267\u884c\u7ed3\u679c\uff1a\na    0\nb    0\nc    0\ndtype: int64\n# \u521b\u5efa\u4e00\u4e2a\u503c\u90fd\u662f0\u7684\u6570\u7ec4\n-----------------------------------------------<\/code><\/pre>\n<p>\u200b   \u5bf9\u4e8eSeries\uff0c\u5176\u5b9e\u6211\u4eec\u53ef\u4ee5\u8ba4\u4e3a\u5b83\u662f\u4e00\u4e2a\u957f\u5ea6\u56fa\u5b9a\u4e14\u6709\u5e8f\u7684\u5b57\u5178\uff0c\u56e0\u4e3a\u5b83\u7684\u7d22\u5f15\u548c\u6570\u636e\u662f\u6309\u4f4d\u7f6e\u8fdb\u884c\u5339\u914d\u7684\uff0c\u50cf\u6211\u4eec\u4f1a\u4f7f\u7528\u5b57\u5178\u7684\u4e0a\u4e0b\u6587\uff0c\u5c31\u80af\u5b9a\u4e5f\u4f1a\u4f7f\u7528Series<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_series_1.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_series_1.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.1.2\u3001\u7f3a\u5931\u6570\u636e<\/h4>\n<ul>\n<li>dropna()  # \u8fc7\u6ee4\u6389\u503c\u4e3aNaN\u7684\u884c<\/li>\n<li>fill()  # \u586b\u5145\u7f3a\u5931\u6570\u636e<\/li>\n<li>isnull()  # \u8fd4\u56de\u5e03\u5c14\u6570\u7ec4\uff0c\u7f3a\u5931\u503c\u5bf9\u5e94\u4e3aTrue<\/li>\n<li>notnull()  # \u8fd4\u56de\u5e03\u5c14\u6570\u7ec4\uff0c\u7f3a\u5931\u503c\u5bf9\u5e94\u4e3aFalse<\/li>\n<\/ul>\n<pre><code class=\"language-python\"># \u7b2c\u4e00\u6b65\uff0c\u521b\u5efa\u4e00\u4e2a\u5b57\u5178\uff0c\u901a\u8fc7Series\u65b9\u5f0f\u521b\u5efa\u4e00\u4e2aSeries\u5bf9\u8c61\n\nst = {&quot;sean&quot;:18,&quot;yang&quot;:19,&quot;bella&quot;:20,&quot;cloud&quot;:21}\nobj = pd.Series(st)\nobj\n\u8fd0\u884c\u7ed3\u679c\uff1a\nsean     18\nyang     19\nbella    20\ncloud    21\ndtype: int64\n------------------------------------------\n# \u7b2c\u4e8c\u6b65\na = {&#039;sean&#039;,&#039;yang&#039;,&#039;cloud&#039;,&#039;rocky&#039;}  # \u5b9a\u4e49\u4e00\u4e2a\u7d22\u5f15\u53d8\u91cf\n------------------------------------------\n#\u7b2c\u4e09\u6b65\nobj1 = pd.Series(st,index=a)\nobj1  # \u5c06\u7b2c\u4e8c\u6b65\u5b9a\u4e49\u7684a\u53d8\u91cf\u4f5c\u4e3a\u7d22\u5f15\u4f20\u5165\n\n# \u8fd0\u884c\u7ed3\u679c\uff1a\nrocky     NaN\ncloud    21.0\nsean     18.0\nyang     19.0\ndtype: float64\n# \u56e0\u4e3arocky\u6ca1\u6709\u51fa\u73b0\u5728st\u7684\u952e\u4e2d\uff0c\u6240\u4ee5\u8fd4\u56de\u7684\u662f\u7f3a\u5931\u503c<\/code><\/pre>\n<p>\u901a\u8fc7\u4e0a\u9762\u7684\u4ee3\u7801\u6f14\u793a\uff0c\u5bf9\u4e8e\u7f3a\u5931\u503c\u5df2\u7ecf\u6709\u4e86\u4e00\u4e2a\u7b80\u5355\u7684\u4e86\u89e3\uff0c\u63a5\u4e0b\u6765\u5c31\u6765\u770b\u770b\u5982\u4f55\u5224\u65ad\u7f3a\u5931\u503c<\/p>\n<pre><code class=\"language-python\">1\u3001\nobj1.isnull()  # \u662f\u7f3a\u5931\u503c\u8fd4\u56deTure\n\u8fd0\u884c\u7ed3\u679c\uff1a\nrocky     True\ncloud    False\nsean     False\nyang     False\ndtype: bool\n\n2\u3001\nobj1.notnull()  # \u4e0d\u662f\u7f3a\u5931\u503c\u8fd4\u56deTure\n\u8fd0\u884c\u7ed3\u679c\uff1a\nrocky    False\ncloud     True\nsean      True\nyang      True\ndtype: bool\n\n3\u3001\u8fc7\u6ee4\u7f3a\u5931\u503c # \u5e03\u5c14\u578b\u7d22\u5f15\nobj1[obj1.notnull()]\n\u8fd0\u884c\u7ed3\u679c\uff1a\ncloud    21.0\nyang     19.0\nsean     18.0\ndtype: float64<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_series_2.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_series_2.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.1.3\u3001Series\u7279\u6027<\/h4>\n<pre><code class=\"language-python\">import numpy as np\nimport pandas as pd<\/code><\/pre>\n<ul>\n<li>\u4ecendarray\u521b\u5efaSeries:Series(arr)<\/li>\n<\/ul>\n<pre><code class=\"language-python\">arr = np.arange(10)\n\nsr = pd.Series(arr)  # ndarray\u521b\u5efaSeries<\/code><\/pre>\n<ul>\n<li>\u4e0e\u6807\u91cf\uff08\u6570\u5b57\uff09\u8fdb\u884c\u8fd0\u7b97\uff1asr * 2<\/li>\n<\/ul>\n<pre><code class=\"language-python\">srx = sr * 2  # \u4e0e\u6807\u91cf\uff08\u6570\u5b57\uff09\u8fdb\u884c\u8fd0\u7b97<\/code><\/pre>\n<ul>\n<li>\u4e24\u4e2aSeries\u8fd0\u7b97<\/li>\n<\/ul>\n<pre><code class=\"language-python\">sr * srx  # \u4e24\u4e2aSeries\u8fd0\u7b97<\/code><\/pre>\n<ul>\n<li>\u5e03\u5c14\u503c\u8fc7\u6ee4\uff1asr[sr&gt;0]<\/li>\n<\/ul>\n<pre><code class=\"language-python\">sr[sr&gt;3]  # \u5e03\u5c14\u503c\u8fc7\u6ee4<\/code><\/pre>\n<ul>\n<li>\u7edf\u8ba1\u51fd\u6570\uff1amean()\u3001sum()\u3001cumsum()<\/li>\n<\/ul>\n<pre><code class=\"language-python\"># \u7edf\u8ba1\u51fd\u6570\nsr.mean()\nsr.sum()\nsr.cumsum()<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_series_3.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_series_3.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.1.4\u3001\u652f\u6301\u5b57\u5178\u7684\u7279\u6027<\/h4>\n<ul>\n<li>\u4ece\u5b57\u5178\u521b\u5efaSeries\uff1aSeries(dic),<\/li>\n<\/ul>\n<pre><code class=\"language-python\">dic = {&quot;A&quot;:1,&quot;B&quot;:2,&quot;C&quot;:3,&quot;D&quot;:4,&quot;E&quot;:5}\n\n# \u5b57\u5178\u521b\u5efaSeries\ndic_arr = pd.Series(dic)  <\/code><\/pre>\n<ul>\n<li>In\u8fd0\u7b97\uff1a&#8217;a&#8217;in sr\u3001for x in sr<\/li>\n<\/ul>\n<pre><code class=\"language-python\">&quot;A&quot; in dic_arr\n------------------------------\nfor i in dic_arr: \n    print(i)<\/code><\/pre>\n<ul>\n<li>\u952e\u7d22\u5f15\uff1asr[&#8216;a&#8217;],sr[[&#8216;a&#8217;,&#8217;b&#8217;,&#8217;d&#8217;]]<\/li>\n<\/ul>\n<pre><code class=\"language-python\">dic_arr[[&#039;A&#039;,&#039;B&#039;]]  # \u952e\u7d22\u5f15<\/code><\/pre>\n<ul>\n<li>\u952e\u5207\u7247\uff1asr[&#8216;a&#8217;:&#8217;c&#8217;]<\/li>\n<\/ul>\n<pre><code class=\"language-python\">dic_arr[&#039;A&#039;:&#039;C&#039;]  # \u952e\u5207\u7247<\/code><\/pre>\n<ul>\n<li>\u5176\u4ed6\u51fd\u6570\uff1aget(&#8216;a&#8217;,default=0)\u7b49<\/li>\n<\/ul>\n<pre><code class=\"language-python\">dic_arr.get(&quot;A&quot;,default=0)  <\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_series_4.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_series_4.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.1.5\u3001\u6574\u6570\u7d22\u5f15<\/h4>\n<p>pandas\u5f53\u4e2d\u7684\u6574\u6570\u7d22\u5f15\u5bf9\u8c61\u53ef\u80fd\u4f1a\u8ba9\u521d\u6b21\u63a5\u89e6\u5b83\u7684\u4eba\u5f88\u61f5\u903c\uff0c\u63a5\u4e0b\u6765\u901a\u8fc7\u4ee3\u7801\u6f14\u793a\uff1a<\/p>\n<pre><code class=\"language-python\">sr = pd.Series(np.arange(10))\nsr1 = sr[3:].copy()\nsr1\n\u8fd0\u884c\u7ed3\u679c\uff1a\n3    3\n4    4\n5    5\n6    6\n7    7\n8    8\n9    9\ndtype: int32\n# \u5230\u8fd9\u91cc\u4f1a\u53d1\u73b0\u5f88\u6b63\u5e38\uff0c\u4e00\u70b9\u95ee\u9898\u90fd\u6ca1\u6709\uff0c\u53ef\u662f\u5f53\u4f7f\u7528\u6574\u6570\u7d22\u5f15\u53d6\u503c\u7684\u65f6\u5019\u5c31\u4f1a\u51fa\u73b0\u95ee\u9898\u4e86\u3002\u56e0\u4e3a\u5728pandas\u5f53\u4e2d\u4f7f\u7528\u6574\u6570\u7d22\u5f15\u53d6\u503c\u662f\u4f18\u5148\u4ee5\u6807\u7b7e\u89e3\u91ca\u7684\uff0c\u800c\u4e0d\u662f\u4e0b\u6807\nsr1[1]<\/code><\/pre>\n<p>\u89e3\u51b3\u65b9\u6cd5\uff1a<\/p>\n<ul>\n<li>loc\u5c5e\u6027  # \u4ee5\u6807\u7b7e\u89e3\u91ca<\/li>\n<li>iloc\u5c5e\u6027  # \u4ee5\u4e0b\u6807\u89e3\u91ca<\/li>\n<\/ul>\n<pre><code class=\"language-python\">sr1.iloc[1]  # \u4ee5\u4e0b\u6807\u89e3\u91ca\n\nsr1.loc[3]  # \u4ee5\u6807\u7b7e\u89e3\u91ca<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_series_5.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_series_5.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.1.6\u3001Series\u6570\u636e\u5bf9\u9f50<\/h4>\n<p>pandas\u5728\u8fd0\u7b97\u65f6\uff0c\u4f1a\u6309\u7d22\u5f15\u8fdb\u884c\u5bf9\u9f50\u7136\u540e\u8ba1\u7b97\u3002\u5982\u679c\u5b58\u5728\u4e0d\u540c\u7684\u7d22\u5f15\uff0c\u5219\u7ed3\u679c\u7684\u7d22\u5f15\u662f\u4e24\u4e2a\u64cd\u4f5c\u6570\u7d22\u5f15\u7684\u5e76\u96c6\u3002<\/p>\n<pre><code class=\"language-python\">sr1 = pd.Series([12,23,34], index=[&#039;c&#039;,&#039;a&#039;,&#039;d&#039;])\nsr2 = pd.Series([11,20,10], index=[&#039;d&#039;,&#039;c&#039;,&#039;a&#039;,])\nsr1 + sr2\n\u8fd0\u884c\u7ed3\u679c:\na    33\nc    32\nd    45\ndtype: int64\n# \u53ef\u4ee5\u901a\u8fc7\u8fd9\u79cd\u7d22\u5f15\u5bf9\u9f50\u76f4\u63a5\u5c06\u4e24\u4e2aSeries\u5bf9\u8c61\u8fdb\u884c\u8fd0\u7b97\nsr3 = pd.Series([11,20,10,14], index=[&#039;d&#039;,&#039;c&#039;,&#039;a&#039;,&#039;b&#039;])\nsr1 + sr3\n\u8fd0\u884c\u7ed3\u679c\uff1a\na    33.0\nb     NaN\nc    32.0\nd    45.0\ndtype: float64\n# sr1 \u548c sr3\u7684\u7d22\u5f15\u4e0d\u4e00\u81f4\uff0c\u6240\u4ee5\u6700\u7ec8\u7684\u8fd0\u884c\u4f1a\u53d1\u73b0b\u7d22\u5f15\u5bf9\u5e94\u7684\u503c\u65e0\u6cd5\u8fd0\u7b97\uff0c\u5c31\u8fd4\u56de\u4e86NaN,\u4e00\u4e2a\u7f3a\u5931\u503c<\/code><\/pre>\n<p>\u5c06\u4e24\u4e2aSeries\u5bf9\u8c61\u76f8\u52a0\u65f6\u5c06\u7f3a\u5931\u503c\u8bbe\u4e3a0\uff1a<\/p>\n<pre><code class=\"language-python\">sr1 = pd.Series([12,23,34], index=[&#039;c&#039;,&#039;a&#039;,&#039;d&#039;])\nsr3 = pd.Series([11,20,10,14], index=[&#039;d&#039;,&#039;c&#039;,&#039;a&#039;,&#039;b&#039;])\nsr1.add(sr3,fill_value=0)\n\u8fd0\u884c\u7ed3\u679c\uff1a\na    33.0\nb    14.0\nc    32.0\nd    45.0\ndtype: float64\n# \u5c06\u7f3a\u5931\u503c\u8bbe\u4e3a0\uff0c\u6240\u4ee5\u6700\u540e\u7b97\u51fa\u6765b\u7d22\u5f15\u5bf9\u5e94\u7684\u7ed3\u679c\u4e3a14<\/code><\/pre>\n<p>\u7075\u6d3b\u7684\u7b97\u672f\u65b9\u6cd5:add,sub,div,mul<\/p>\n<p>\u5230\u8fd9\u91cc\u53ef\u80fd\u5c31\u4f1a\u8bf4\u4e86pandas\u5c31\u8fd9\u4e48\u7b80\u5355\u5417\uff0c\u90a3\u6211\u4eec\u63a5\u4e0b\u6765\u4e00\u8d77\u770b\u770b\u8fd9\u4e2a\u4e8c\u7ef4\u6570\u7ec4DataFraeme<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_series_6.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_series_6.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h3>3.2\u3001DataFrame<\/h3>\n<p>\u200b   DataFrame\u662f\u4e00\u4e2a\u8868\u683c\u578b\u7684\u6570\u636e\u7ed3\u6784\uff0c\u76f8\u5f53\u4e8e\u662f\u4e00\u4e2a\u4e8c\u7ef4\u6570\u7ec4\uff0c\u542b\u6709\u4e00\u7ec4\u6709\u5e8f\u7684\u5217\u3002\u4ed6\u53ef\u4ee5\u88ab\u770b\u505a\u662f\u7531Series\u7ec4\u6210\u7684\u5b57\u5178\uff0c\u5e76\u4e14\u5171\u7528\u4e00\u4e2a\u7d22\u5f15\u3002\u63a5\u4e0b\u6765\u5c31\u4e00\u8d77\u6765\u89c1\u8bc6\u89c1\u8bc6DataFrame\u6570\u7ec4\u7684\u5389\u5bb3\u5427\uff01\uff01\uff01<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_df_1.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_df_1.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.2.1\u3001\u521b\u5efa\u65b9\u5f0f<\/h4>\n<p>\u521b\u5efa\u4e00\u4e2aDataFrame\u6570\u7ec4\u53ef\u4ee5\u6709\u591a\u79cd\u65b9\u5f0f\uff0c\u5176\u4e2d\u6700\u4e3a\u5e38\u7528\u7684\u65b9\u5f0f\u5c31\u662f\u5229\u7528\u5305\u542b\u7b49\u957f\u5ea6\u5217\u8868\u6216Numpy\u6570\u7ec4\u7684\u5b57\u5178\u6765\u5f62\u6210DataFrame\uff1a<\/p>\n<pre><code class=\"language-python\">\u7b2c\u4e00\u79cd\uff1a\npd.DataFrame({&#039;one&#039;:[1,2,3,4],&#039;two&#039;:[4,3,2,1]})\n# \u4ea7\u751f\u7684DataFrame\u4f1a\u81ea\u52a8\u4e3aSeries\u5206\u914d\u6240\u7d22\u5f15\uff0c\u5e76\u4e14\u5217\u4f1a\u6309\u7167\u6392\u5e8f\u7684\u987a\u5e8f\u6392\u5217\n\u8fd0\u884c\u7ed3\u679c\uff1a\n    one two\n0   1   4\n1   2   3\n2   3   2\n3   4   1\n\n> \u6307\u5b9a\u5217\n\u53ef\u4ee5\u901a\u8fc7columns\u53c2\u6570\u6307\u5b9a\u987a\u5e8f\u6392\u5217\ndata = pd.DataFrame({&#039;one&#039;:[1,2,3,4],&#039;two&#039;:[4,3,2,1]})\npd.DataFrame(data,columns=[&#039;one&#039;,&#039;two&#039;])\n\n# \u6253\u5370\u7ed3\u679c\u4f1a\u6309\u7167columns\u53c2\u6570\u6307\u5b9a\u987a\u5e8f\n\n\u7b2c\u4e8c\u79cd\uff1a\npd.DataFrame({&#039;one&#039;:pd.Series([1,2,3],index=[&#039;a&#039;,&#039;b&#039;,&#039;c&#039;]),&#039;two&#039;:pd.Series([1,2,3],index=[&#039;b&#039;,&#039;a&#039;,&#039;c&#039;])})\n\u8fd0\u884c\u7ed3\u679c\uff1a\n   one  two\na   1   2\nb   2   1\nc   3   3<\/code><\/pre>\n<p>\u4ee5\u4e0a\u521b\u5efa\u65b9\u6cd5\u7b80\u5355\u4e86\u89e3\u5c31\u53ef\u4ee5\uff0c\u56e0\u4e3a\u5728\u5b9e\u9645\u5e94\u7528\u5f53\u4e2d\u66f4\u591a\u662f\u8bfb\u6570\u636e\uff0c\u4e0d\u9700\u8981\u81ea\u5df1\u624b\u52a8\u521b\u5efa<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_df_2.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_df_2.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.2.2\u3001\u67e5\u770b\u6570\u636e<\/h4>\n<p>\u5e38\u7528\u5c5e\u6027\u548c\u65b9\u6cd5\uff1a<\/p>\n<ul>\n<li>index    \u83b7\u53d6\u884c\u7d22\u5f15<\/li>\n<li>columns  \u83b7\u53d6\u5217\u7d22\u5f15<\/li>\n<li>T        \u8f6c\u7f6e<\/li>\n<li>values   \u83b7\u53d6\u503c\u7d22\u5f15<\/li>\n<li>describe \u83b7\u53d6\u5feb\u901f\u7edf\u8ba1<\/li>\n<\/ul>\n<pre><code class=\"language-python\"> one    two\na   1   2\nb   2   1\nc   3   3\n# \u8fd9\u6837\u4e00\u4e2a\u6570\u7ec4df\n---------------------------------------------------------------------------\ndf.index\n\n> Index([&#039;a&#039;, &#039;b&#039;, &#039;c&#039;], dtype=&#039;object&#039;)\n---------------------------------------------------------------------------\ndf.columns\n\n> Index([&#039;one&#039;, &#039;two&#039;], dtype=&#039;object&#039;)\n--------------------------------------------------------------------------\ndf.T\n\n>    a  b   c\none 1   2   3\ntwo 2   1   3\n\n-------------------------------------------------------------------------\ndf.values\n\n> array([[1, 2],\n       [2, 1],\n       [3, 3]], dtype=int64)\n------------------------------------------------------------------------\ndf.describe()\n\n>       one two\ncount   3.0 3.0   # \u6570\u636e\u7edf\u8ba1\nmean    2.0 2.0   # \u5e73\u5747\u503c\nstd     1.0 1.0   # \u6807\u51c6\u5dee\nmin     1.0 1.0   # \u6700\u5c0f\u503c\n25%     1.5 1.5   # \u56db\u5206\u4e4b\u4e00\u5747\u503c\n50%     2.0 2.0   # \u4e8c\u5206\u4e4b\u4e00\u5747\u503c\n75%     2.5 2.5   # \u56db\u5206\u4e4b\u4e09\u5747\u503c\nmax     3.0 3.0   # \u6700\u5927\u503c<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_df_3.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_df_3.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.2.3\u3001\u7d22\u5f15\u548c\u5207\u7247<\/h4>\n<ul>\n<li>DataFrame\u6709\u884c\u7d22\u5f15\u548c\u5217\u7d22\u5f15\u3002<\/li>\n<li>DataFrame\u540c\u6837\u53ef\u4ee5\u901a\u8fc7\u6807\u7b7e\u548c\u4f4d\u7f6e\u4e24\u79cd\u65b9\u6cd5\u8fdb\u884c\u7d22\u5f15\u548c\u5207\u7247\u3002<\/li>\n<\/ul>\n<p>DataFrame\u4f7f\u7528\u7d22\u5f15\u5207\u7247\uff1a<\/p>\n<ul>\n<li>\u65b9\u6cd51\uff1a\u4e24\u4e2a\u4e2d\u62ec\u53f7\uff0c\u65e0\u8bba\u662f\u5148\u53d6\u884c\u8fd8\u662f\u5148\u53d6\u5217\u90fd\u53ef\u4ee5\u3002<\/li>\n<\/ul>\n<pre><code class=\"language-python\">import tushare as ts\n\ndata = ts.get_k_data(&quot;000001&quot;)\n\ndata[&#039;open&#039;][:10]  # \u5148\u53d6\u5217\u518d\u53d6\u884c\ndata[:10][&#039;open&#039;]  # \u5148\u53d6\u884c\u518d\u53d6\u5217<\/code><\/pre>\n<ul>\n<li>\u65b9\u6cd52\uff08\u63a8\u8350\uff09\uff1a\u4f7f\u7528loc\/iloc\u5c5e\u6027\uff0c\u4e00\u4e2a\u4e2d\u62ec\u53f7\uff0c\u9017\u53f7\u9694\u5f00\uff0c\u5148\u53d6\u884c\u518d\u53d6\u5217\u3002\n<ul>\n<li>loc\u5c5e\u6027\uff1a\u89e3\u91ca\u4e3a\u6807\u7b7e<\/li>\n<li>iloc\u5c5e\u6027\uff1a\u89e3\u91ca\u4e3a\u4e0b\u6807<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<pre><code class=\"language-python\">data.loc[:10,&quot;open&quot;:&quot;low&quot;]  # \u7528\u6807\u7b7e\u53d6\u503c\n\ndata.iloc[:10,1:5]  # \u7528\u4e0b\u6807\u53d6\u503c<\/code><\/pre>\n<ul>\n<li>\u5411DataFrame\u5bf9\u8c61\u4e2d\u5199\u5165\u503c\u65f6\u53ea\u4f7f\u7528\u65b9\u6cd52<\/li>\n<li>\u884c\/\u5217\u7d22\u5f15\u90e8\u5206\u53ef\u4ee5\u662f\u5e38\u89c4\u7d22\u5f15\u3001\u5207\u7247\u3001\u5e03\u5c14\u503c\u7d22\u5f15\u3001\u82b1\u5f0f\u7d22\u5f15\u4efb\u610f\u642d\u914d\u3002\uff08\u6ce8\u610f\uff1a\u4e24\u90e8\u5206\u90fd\u662f\u82b1\u5f0f\u7d22\u5f15\u65f6\u7ed3\u679c\u53ef\u80fd\u4e0e\u9884\u6599\u7684\u4e0d\u540c\uff09<\/li>\n<\/ul>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_df_4.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_df_4.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h3>3.3\u3001\u65f6\u95f4\u5bf9\u8c61\u5904\u7406<\/h3>\n<p>\u200b   \u5904\u7406\u65f6\u95f4\u5bf9\u8c61\u53ef\u80fd\u662f\u6211\u4eec\u5728\u8fdb\u884c\u6570\u636e\u5206\u6790\u7684\u8fc7\u7a0b\u5f53\u4e2d\u6700\u5e38\u89c1\u7684\uff0c\u6211\u4eec\u4f1a\u9047\u5230\u5404\u79cd\u683c\u5f0f\u7684\u65f6\u95f4\u5e8f\u5217\uff0c\u4e5f\u9700\u8981\u5904\u7406\u5404\u79cd\u683c\u5f0f\u7684\u65f6\u95f4\u5e8f\u5217\uff0c\u4f46\u662f\u4e00\u5b9a\u4e0d\u80fd\u5bf9\u8fd9\u4e9b\u6570\u636e\u61f5\u903c\uff0c\u6211\u4eec\u9700\u8981\u627e\u5230\u6700\u5408\u9002\u7684\u62db\u5f0f\u6765\u5904\u7406\u8fd9\u4e9b\u65f6\u95f4\u3002\u63a5\u4e0b\u6765\u5c31\u4e00\u8d77\u6765\u770b\u5427\uff01\uff01\uff01<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_1.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_1.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.3.1\u3001\u65f6\u95f4\u5e8f\u5217\u7c7b\u578b<\/h4>\n<ul>\n<li>\u65f6\u95f4\u6233\uff1a\u7279\u5b9a\u65f6\u523b<\/li>\n<li>\u56fa\u5b9a\u65f6\u671f\uff1a\u59822019\u5e741\u6708<\/li>\n<li>\u65f6\u95f4\u95f4\u9694\uff1a\u8d77\u59cb\u65f6\u95f4-\u7ed3\u675f\u65f6\u95f4<\/li>\n<\/ul>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_2.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_2.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.3.2\u3001Python\u5e93\uff1adatatime<\/h4>\n<ul>\n<li>date\u3001datetime\u3001timedelta<\/li>\n<\/ul>\n<pre><code class=\"language-python\">import datetime\n\n# datetime.date()  # date\u5bf9\u8c61\n\ntoday = datetime.date.today()  # \u83b7\u53d6\u5f53\u5929\u65e5\u671f\uff0c\u8fd4\u56dedate\u5bf9\u8c61\nt1 = datetime.date(2019,4,18) # \u8bbe\u7f6e\u65f6\u95f4\u683c\u5f0f\u4e3adatetime.date\n\n# datetime.datetime()  # datetime\u5bf9\u8c61\n\nnow = datetime.datetime.now()  # \u83b7\u53d6\u5f53\u5929\u65e5\u671f\uff0c\u8fd4\u56dedatetime\u5bf9\u8c61\nt2 = datetime.datetime(2019,4,18) # \u8bbe\u7f6e\u65f6\u95f4\u683c\u5f0f\u4e3adatetime.datetime\n\n# datetime.timedelta()  # \u65f6\u95f4\u5dee\n\ntoday = datetime.datetime.today()\nyestoday = today - datetime.timedelta(1)  # \u4ee5\u65f6\u95f4\u505a\u8fd0\u7b97\nprint(today,yestoday)<\/code><\/pre>\n<ul>\n<li>dt.strftime()<\/li>\n<\/ul>\n<pre><code class=\"language-python\"># \u5c06\u65f6\u95f4\u683c\u5f0f\u8f6c\u6362\u4e3a\u5b57\u7b26\u4e32\ntoday.strftime(&quot;%Y-%m-%d&quot;)\nyestoday.strftime(&quot;%Y-%m-%d&quot;)<\/code><\/pre>\n<ul>\n<li>strptime()<\/li>\n<\/ul>\n<pre><code class=\"language-python\"># \u5c06\u65e5\u671f\u5b57\u7b26\u4e32\u8f6c\u6210datetime\u65f6\u95f4\u683c\u5f0f\uff0c\u7b2c\u4e8c\u4e2a\u53c2\u6570\u7531\u65f6\u95f4\u683c\u5f0f\u51b3\u5b9a\ndatetime.datetime.strptime(&#039;2019-04-18&#039;,&#039;%Y-%m-%d&#039;)<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_3.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_3.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.3.3\u3001\u7075\u6d3b\u5904\u7406\u65f6\u95f4\u5bf9\u8c61\uff1adateutil\u5305<\/h4>\n<ul>\n<li>dateutil.parser.parse()<\/li>\n<\/ul>\n<pre><code class=\"language-python\">import dateutil\n\n# \u5c06\u5b57\u7b26\u4e32\u683c\u5f0f\u7684\u65e5\u671f\u8f6c\u6362\u4e3adatetime\u5bf9\u8c61\ndate = &#039;2019 Jan 2nd&#039;\nt3 = dateutil.parser.parse(date)<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_4.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_4.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.3.4\u3001\u6210\u7ec4\u5904\u7406\u65f6\u95f4\u5bf9\u8c61\uff1apandas<\/h4>\n<ul>\n<li>pd.to_datetime([&#8216;2018-01-01&#8217;, &#8216;2019-02-02&#8217;])<\/li>\n<\/ul>\n<p>\u5c06\u5b57\u7b26\u4e32\u8f6c\u6362\u4e3a\u4e3a\u65f6\u95f4\u5bf9\u8c61<\/p>\n<pre><code class=\"language-python\">from datetime import datetime\nimport pandas as pd\n\ndate1 = datetime(2019, 4, 18, 12, 24, 30)\ndate2 = &#039;2019-04-18&#039;\nt4 = pd.to_datetime(date1)\nt5 = pd.to_datetime(date2)\nt6 = pd.to_datetime([date1,date2])\n\nt4,t5,t6  # \u8f6c\u6362\u5355\u4e2a\u65f6\u95f4\u6570\u636e\u662f\u8fd4\u56deTimestamp\u5bf9\u8c61\uff0c\u8f6c\u6362\u591a\u4e2a\u65f6\u95f4\u6570\u636e\u8fd4\u56deDatetimeIndex\u5bf9\u8c61\n> \n&quot;&quot;&quot;\n(Timestamp(&#039;2019-04-18 12:24:30&#039;),\n Timestamp(&#039;2019-04-18 00:00:00&#039;),\n DatetimeIndex([&#039;2019-04-18 12:24:30&#039;, &#039;2019-04-18 00:00:00&#039;], dtype=&#039;datetime64[ns]&#039;, freq=None))\n&quot;&quot;&quot;<\/code><\/pre>\n<p>\u5c06\u7d22\u5f15\u8bbe\u7f6e\u4e3a\u65f6\u95f4\u5e8f\u5217<\/p>\n<pre><code class=\"language-python\">ind = pd.to_datetime([&#039;2018-03-01&#039;,&#039;2019 Feb 3&#039;,&#039;08\/12-\/019&#039;])\nsr = pd.Series([1,2,3],index=ind)\n\n# \u8865\u5145\uff1a\n&quot;&quot;&quot;\npd.to_datetime([&#039;2018-03-01&#039;,&#039;2019 Feb 3&#039;,&#039;08\/12-\/019&#039;]).to_pydatetime()\n\n> array([datetime.datetime(2018, 3, 1, 0, 0),\n       datetime.datetime(2019, 2, 3, 0, 0),\n       datetime.datetime(2019, 8, 12, 0, 0)], dtype=object)\n# \u901a\u8fc7to_pydatetime()\u65b9\u6cd5\u5c06\u5176\u8f6c\u6362\u4e3andarray\u6570\u7ec4\n&quot;&quot;&quot;<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_5.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_5.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.3.5\u3001\u4ea7\u751f\u65f6\u95f4\u5bf9\u8c61\u6570\u7ec4\uff1adata_range<\/h4>\n<ul>\n<li>start     \u5f00\u59cb\u65f6\u95f4<\/li>\n<li>end       \u7ed3\u675f\u65f6\u95f4<\/li>\n<li>periods       \u65f6\u95f4\u957f\u5ea6<\/li>\n<li>freq      \u65f6\u95f4\u9891\u7387\uff0c\u9ed8\u8ba4\u4e3a&#8217;D&#8217;\uff0c\u53ef\u9009H(our),W(eek),B(usiness),S(emi-)M(onth),(min)T(es), S(econd), A(year),\u2026<\/li>\n<\/ul>\n<pre><code class=\"language-python\">pd.date_range(&quot;2019-1-1&quot;,&quot;2019-2-2&quot;,freq=&quot;D&quot;)\n\n> DatetimeIndex([&#039;2019-01-01&#039;, &#039;2019-01-02&#039;, &#039;2019-01-03&#039;, &#039;2019-01-04&#039;,\n               &#039;2019-01-05&#039;, &#039;2019-01-06&#039;, &#039;2019-01-07&#039;, &#039;2019-01-08&#039;,\n               &#039;2019-01-09&#039;, &#039;2019-01-10&#039;, &#039;2019-01-11&#039;, &#039;2019-01-12&#039;,\n               &#039;2019-01-13&#039;, &#039;2019-01-14&#039;, &#039;2019-01-15&#039;, &#039;2019-01-16&#039;,\n               &#039;2019-01-17&#039;, &#039;2019-01-18&#039;, &#039;2019-01-19&#039;, &#039;2019-01-20&#039;,\n               &#039;2019-01-21&#039;, &#039;2019-01-22&#039;, &#039;2019-01-23&#039;, &#039;2019-01-24&#039;,\n               &#039;2019-01-25&#039;, &#039;2019-01-26&#039;, &#039;2019-01-27&#039;, &#039;2019-01-28&#039;,\n               &#039;2019-01-29&#039;, &#039;2019-01-30&#039;, &#039;2019-01-31&#039;, &#039;2019-02-01&#039;,\n               &#039;2019-02-02&#039;],\n              dtype=&#039;datetime64[ns]&#039;, freq=&#039;D&#039;)<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_6.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_6.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.3.6\u3001\u65f6\u95f4\u5e8f\u5217<\/h4>\n<p>\u65f6\u95f4\u5e8f\u5217\u5c31\u662f\u4ee5\u65f6\u95f4\u5bf9\u8c61\u4e3a\u7d22\u5f15\u7684Series\u6216DataFrame\u3002datetime\u5bf9\u8c61\u4f5c\u4e3a\u7d22\u5f15\u65f6\u662f\u5b58\u50a8\u5728DatetimeIndex\u5bf9\u8c61\u4e2d\u7684\u3002<\/p>\n<pre><code class=\"language-python\"># \u8f6c\u6362\u65f6\u95f4\u7d22\u5f15\ndt = pd.date_range(&quot;2019-01-01&quot;,&quot;2019-02-02&quot;)\n# \u751f\u6210\u4e00\u4e2a\u5e26\u6709\u65f6\u95f4\u6570\u636e\u7684DataFrame\u6570\u7ec4\na = pd.DataFrame({&quot;num&quot;:pd.Series(random.randint(-100,100) for _ in range(30)),&quot;date&quot;:dt})\n# \u901a\u8fc7index\u4fee\u6539\u7d22\u5f15\na.index = pd.to_datetime(a[&quot;date&quot;])<\/code><\/pre>\n<p>\u7279\u6b8a\u529f\u80fd\uff1a<\/p>\n<ul>\n<li>\u4f20\u5165\u201c\u5e74\u201d\u6216\u201c\u5e74\u6708\u201d\u4f5c\u4e3a\u5207\u7247\u65b9\u5f0f<\/li>\n<li>\u4f20\u5165\u65e5\u671f\u8303\u56f4\u4f5c\u4e3a\u5207\u7247\u65b9\u5f0f<\/li>\n<li>\u4e30\u5bcc\u7684\u51fd\u6570\u652f\u6301\uff1aresample(), strftime(), \u2026\u2026<\/li>\n<\/ul>\n<pre><code class=\"language-python\">a.resample(&quot;3D&quot;).mean()  # \u8ba1\u7b97\u6bcf\u4e09\u5929\u7684\u5747\u503c\na.resample(&quot;3D&quot;).sum()  #  \u8ba1\u7b97\u6bcf\u4e09\u5929\u7684\u548c\n...<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_7.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_7.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u200b   \u65f6\u95f4\u5e8f\u5217\u7684\u5904\u7406\u5728\u6570\u636e\u5206\u6790\u5f53\u4e2d\u975e\u5e38\u91cd\u8981\uff0c\u4f46\u662f\u6709\u65f6\u5019\u65f6\u95f4\u7684\u683c\u5f0f\u4e0d\u4e00\u81f4\u53c8\u4f1a\u8ba9\u4eba\u975e\u5e38\u70e6\u8e81\uff0c\u53ea\u8981\u628a\u4ee5\u4e0a\u79d8\u7c4d\u90fd\u5b66\u4f1a\u5c31\u53ef\u4ee5\u628a\u65f6\u95f4\u5e8f\u5217\u5236\u5f97\u670d\u670d\u5e16\u5e16\u3002<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_8.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_time_8.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h3>3.4\u3001\u6570\u636e\u5206\u7ec4\u548c\u805a\u5408<\/h3>\n<p>\u200b   \u5728\u6570\u636e\u5206\u6790\u5f53\u4e2d\uff0c\u6211\u4eec\u6709\u65f6\u9700\u8981\u5c06\u6570\u636e\u62c6\u5206\uff0c\u7136\u540e\u5728\u6bcf\u4e00\u4e2a\u7279\u5b9a\u7684\u7ec4\u91cc\u8fdb\u884c\u8fd0\u7b97\uff0c\u8fd9\u4e9b\u64cd\u4f5c\u901a\u5e38\u4e5f\u662f\u6570\u636e\u5206\u6790\u5de5\u4f5c\u4e2d\u7684\u91cd\u8981\u73af\u8282\u3002<br \/>\n\u5206\u7ec4\u805a\u5408\u76f8\u5bf9\u6765\u8bf4\u4e5f\u662f\u4e00\u4e2a\u7a0d\u5fae\u96be\u7406\u89e3\u7684\u70b9\uff0c\u9700\u8981\u5404\u4f4d\u6709\u4e00\u5b9a\u7684\u529f\u529b\u6765\u5b66\u4e60.<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_gp_1.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_gp_1.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.4.1\u3001\u5206\u7ec4(GroupBY\u673a\u5236)<\/h4>\n<p>\u200b   pandas\u5bf9\u8c61\uff08\u65e0\u8bbaSeries\u3001DataFrame\u8fd8\u662f\u5176\u4ed6\u7684\u4ec0\u4e48\uff09\u5f53\u4e2d\u7684\u6570\u636e\u4f1a\u6839\u636e\u63d0\u4f9b\u7684\u4e00\u4e2a\u6216\u8005\u591a\u4e2a\u952e\u88ab\u62c6\u5206\u4e3a\u591a\u7ec4\uff0c\u62c6\u5206\u64cd\u4f5c\u5b9e\u5728\u5bf9\u8c61\u7684\u7279\u5b9a\u8f74\u4e0a\u6267\u884c\u7684\u3002\u5c31\u6bd4\u5982DataFrame\u53ef\u4ee5\u5728\u4ed6\u7684\u884c\u4e0a\u6216\u8005\u5217\u4e0a\u8fdb\u884c\u5206\u7ec4\uff0c\u7136\u540e\u5c06\u4e00\u4e2a\u51fd\u6570\u5e94\u7528\u5230\u5404\u4e2a\u5206\u7ec4\u4e0a\u5e76\u4ea7\u751f\u4e00\u4e2a\u65b0\u7684\u503c\u3002\u6700\u540e\u5c06\u6240\u6709\u7684\u6267\u884c\u7ed3\u679c\u5408\u5e76\u5230\u6700\u7ec8\u7684\u7ed3\u679c\u5bf9\u8c61\u4e2d\u3002<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/\u5206\u7ec4\u805a\u5408\u6837\u4f8b.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/\u5206\u7ec4\u805a\u5408\u6837\u4f8b.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u5206\u7ec4\u952e\u53ef\u4ee5\u662f\u591a\u79cd\u6837\u5f0f\uff0c\u5e76\u4e14\u952e\u4e0d\u4e00\u5b9a\u662f\u5b8c\u5168\u76f8\u540c\u7684\u7c7b\u578b\uff1a<\/p>\n<ul>\n<li>\u5217\u8868\u6216\u8005\u6570\u7ec4\uff0c\u957f\u5ea6\u8981\u4e0e\u5f85\u5206\u7ec4\u7684\u8f74\u4e00\u6837<\/li>\n<li>\u8868\u793aDataFrame\u67d0\u4e2a\u5217\u540d\u7684\u503c\u3002<\/li>\n<li>\u5b57\u5178\u6216Series\uff0c\u7ed9\u51fa\u5f85\u5206\u7ec4\u8f74\u4e0a\u7684\u503c\u4e0e\u5206\u7ec4\u540d\u4e4b\u95f4\u7684\u5bf9\u5e94\u5173\u7cfb<\/li>\n<li>\u51fd\u6570\uff0c\u7528\u4e8e\u5904\u7406\u8f74\u7d22\u5f15\u6216\u8005\u7d22\u5f15\u4e2d\u7684\u5404\u4e2a\u6807\u7b7e<\/li>\n<\/ul>\n<p>\u540e\u4e09\u79cd\u53ea\u662f\u5feb\u6377\u65b9\u5f0f\uff0c\u6700\u7ec8\u4ecd\u7136\u662f\u4e3a\u4e86\u4ea7\u751f\u4e00\u7ec4\u7528\u4e8e\u62c6\u5206\u5bf9\u8c61\u7684\u503c\u3002<\/p>\n<p>\u9996\u5148\uff0c\u901a\u8fc7\u4e00\u4e2a\u5f88\u7b80\u5355\u7684DataFrame\u6570\u7ec4\u5c1d\u8bd5\u4e00\u4e0b\uff1a<\/p>\n<pre><code class=\"language-python\">df = pd.DataFrame({&#039;key1&#039;:[&#039;x&#039;,&#039;x&#039;,&#039;y&#039;,&#039;y&#039;,&#039;x&#039;,                               \n            &#039;key2&#039;:[&#039;one&#039;,&#039;two&#039;,&#039;one&#039;,&#039;,two&#039;,&#039;one&#039;],\n            &#039;data1&#039;:np.random.randn(5),\n            &#039;data2&#039;:np.random.randn(5)})\ndf\n\n>   key1    key2    data1   data2\n0   x   one 0.951762    1.632336\n1   x   two -0.369843   0.602261\n2   y   one 1.512005    1.331759\n3   y   two 1.383214    1.025692\n4   x   one -0.475737   -1.182826<\/code><\/pre>\n<p>\u8bbf\u95eedata1\uff0c\u5e76\u6839\u636ekey1\u8c03\u7528groupby\uff1a<\/p>\n<pre><code class=\"language-python\">f1 = df[&#039;data1&#039;].groupby(df[&#039;key1&#039;])\nf1\n\n> &lt;pandas.core.groupby.groupby.SeriesGroupBy object at 0x00000275906596D8&gt;<\/code><\/pre>\n<p>\u4e0a\u8ff0\u8fd0\u884c\u662f\u6ca1\u6709\u8fdb\u884c\u4efb\u4f55\u8ba1\u7b97\u7684\uff0c\u4f46\u662f\u6211\u4eec\u60f3\u8981\u7684\u4e2d\u95f4\u6570\u636e\u5df2\u7ecf\u62ff\u5230\u4e86\uff0c\u63a5\u4e0b\u6765\uff0c\u5c31\u53ef\u4ee5\u8c03\u7528groupby\u8fdb\u884c\u4efb\u4f55\u8ba1\u7b97<\/p>\n<pre><code class=\"language-python\">f1.mean()  # \u8c03\u7528mean\u51fd\u6570\u6c42\u51fa\u5e73\u5747\u503c\n> key1\n    x    0.106183\n    y    2.895220\n    Name: data1, dtype: float64<\/code><\/pre>\n<p>\u4ee5\u4e0a\u6570\u636e\u7ecf\u8fc7\u5206\u7ec4\u952e\uff08\u4e00\u4e2aSeries\u6570\u7ec4\uff09\u8fdb\u884c\u4e86\u805a\u5408\uff0c\u4ea7\u751f\u4e86\u4e00\u4e2a\u65b0\u7684Series\uff0c\u7d22\u5f15\u5c31\u662f<code>key1<\/code>\u5217\u4e2d\u7684\u552f\u4e00\u503c\u3002\u8fd9\u4e9b\u7d22\u5f15\u7684\u540d\u79f0\u5c31\u4e3a<code>key1<\/code>\u3002\u63a5\u4e0b\u6765\u5c31\u5c1d\u8bd5\u4e00\u6b21\u5c06\u591a\u4e2a\u6570\u7ec4\u7684\u5217\u8868\u4f20\u8fdb\u6765<\/p>\n<pre><code class=\"language-python\">f2 = df[&#039;data1&#039;].groupby([df[&#039;key1&#039;],df[&#039;key2&#039;]])\nf2.mean()\n> key1  key2\n    x     one     0.083878\n          two     0.872437\n    y     one    -0.665888\n          two    -0.144310\n    Name: data1, dtype: float64\n<\/code><\/pre>\n<p>\u4f20\u5165\u591a\u4e2a\u6570\u636e\u4e4b\u540e\u4f1a\u53d1\u73b0\uff0c\u5f97\u5230\u7684\u6570\u636e\u5177\u6709\u4e00\u4e2a\u5c42\u6b21\u5316\u7684\u7d22\u5f15\uff0ckey1\u5bf9\u5e94\u7684x\\y;key2\u5bf9\u5e94\u7684one\\two.<\/p>\n<pre><code class=\"language-python\">f2.mean().unstack()  # \u901a\u8fc7unstack\u65b9\u6cd5\u5c31\u53ef\u4ee5\u8ba9\u7d22\u5f15\u4e0d\u5806\u53e0\u5728\u4e00\u8d77\u4e86\n\n> key2  one     two\nkey1        \nx   0.083878    0.872437\ny   -0.665888   -0.144310\n<\/code><\/pre>\n<p>\u8865\u5145\uff1a<\/p>\n<ul>\n<li>1\u3001\u5206\u7ec4\u952e\u53ef\u4ee5\u662f\u4efb\u610f\u957f\u5ea6\u7684\u6570\u7ec4<\/li>\n<li>2\u3001\u5206\u7ec4\u65f6\uff0c\u5bf9\u4e8e\u4e0d\u662f\u6570\u7ec4\u6570\u636e\u7684\u5217\u4f1a\u4ece\u7ed3\u679c\u4e2d\u6392\u9664\uff0c\u4f8b\u5982key1\u3001key2\u8fd9\u6837\u7684\u5217<\/li>\n<li>3\u3001GroupBy\u7684size\u65b9\u6cd5\uff0c\u8fd4\u56de\u4e00\u4e2a\u542b\u6709\u5206\u7ec4\u5927\u5c0f\u7684Series<\/li>\n<\/ul>\n<pre><code class=\"language-python\"># \u4ee5\u4e0a\u9762\u7684f2\u6d4b\u8bd5\nf2.size()\n> key1  key2\nx     one     2\n      two     1\ny     one     1\n      two     1\nName: data1, dtype: int64<\/code><\/pre>\n<p>\u5230\u8fd9\u8ddf\u7740\u6211\u4e0a\u9762\u7684\u6b65\u9aa4\u4e00\u6b65\u4e00\u6b65\u7684\u5206\u6790\uff0c\u4f1a\u53d1\u73b0\u8fd8\u662f\u5f88\u7b80\u5355\u7684\uff0c\u4f46\u662f\u4e00\u5b9a\u4e0d\u80fd\u5e72\u770b\uff0c\u8fd8\u8981\u81ea\u5df1\u4e0b\u624b\u7ec3\uff0c\u53ea\u6709\u591a\u7ec3\u624d\u80fd\u878d\u6c47\u8d2f\u901a\uff01\uff01\uff01<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_gp_2.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_gp_2.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h4>3.4.2\u3001\u805a\u5408(\u7ec4\u5185\u5e94\u7528\u67d0\u4e2a\u51fd\u6570)<\/h4>\n<p>\u805a\u5408\u662f\u6307\u4efb\u4f55\u80fd\u591f\u4ece\u6570\u7ec4\u4ea7\u751f\u6807\u91cf\u503c\u7684\u6570\u636e\u8f6c\u6362\u8fc7\u7a0b\u3002\u521a\u624d\u4e0a\u9762\u7684\u64cd\u4f5c\u4f1a\u53d1\u73b0\u4f7f\u7528GroupBy\u5e76\u4e0d\u4f1a\u76f4\u63a5\u5f97\u5230\u4e00\u4e2a\u663e\u6027\u7684\u7ed3\u679c\uff0c\u800c\u662f\u4e00\u4e2a\u4e2d\u95f4\u6570\u636e\uff0c\u53ef\u4ee5\u901a\u8fc7\u6267\u884c\u7c7b\u4f3cmean\u3001count\u3001min\u7b49\u8ba1\u7b97\u5f97\u51fa\u7ed3\u679c\uff0c\u5e38\u89c1\u7684\u8fd8\u6709\u4e00\u4e9b:<\/p>\n<table>\n<thead>\n<tr>\n<th>\u51fd\u6570\u540d<\/th>\n<th style=\"text-align: center;\">\u63cf\u8ff0<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>sum<\/td>\n<td style=\"text-align: center;\">\u975eNA\u503c\u7684\u548c<\/td>\n<\/tr>\n<tr>\n<td>median<\/td>\n<td style=\"text-align: center;\">\u975eNA\u503c\u7684\u7b97\u672f\u4e2d\u4f4d\u6570<\/td>\n<\/tr>\n<tr>\n<td>std\u3001var<\/td>\n<td style=\"text-align: center;\">\u65e0\u504f\uff08\u5206\u6bcd\u4e3an-1\uff09\u6807\u51c6\u5dee\u548c\u65b9\u5dee<\/td>\n<\/tr>\n<tr>\n<td>prod<\/td>\n<td style=\"text-align: center;\">\u975eNA\u503c\u7684\u79ef<\/td>\n<\/tr>\n<tr>\n<td>first\u3001last<\/td>\n<td style=\"text-align: center;\">\u7b2c\u4e00\u4e2a\u548c\u6700\u540e\u4e00\u4e2a\u975eNA\u503c<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<blockquote>\n<p>\u81ea\u5b9a\u4e49\u805a\u5408\u51fd\u6570<\/p>\n<\/blockquote>\n<p>\u4e0d\u4ec5\u53ef\u4ee5\u4f7f\u7528\u8fd9\u4e9b\u5e38\u7528\u7684\u805a\u5408\u8fd0\u7b97\uff0c\u8fd8\u53ef\u4ee5\u81ea\u5df1\u81ea\u5b9a\u4e49\u3002<\/p>\n<pre><code class=\"language-python\"># \u4f7f\u7528\u81ea\u5b9a\u4e49\u7684\u805a\u5408\u51fd\u6570\uff0c\u9700\u8981\u5c06\u5176\u4f20\u5165aggregate\u6216\u8005agg\u65b9\u6cd5\u5f53\u4e2d\n\ndef peak_to_peak(arr):\n    return arr.max() - arr.min()\nf1.aggregate(peak_to_peak)\n\u8fd0\u884c\u7ed3\u679c\uff1a\nkey1\nx    3.378482\ny    1.951752\nName: data1, dtype: float64<\/code><\/pre>\n<p>\u591a\u51fd\u6570\u805a\u5408\uff1a<\/p>\n<pre><code class=\"language-python\">f1.agg([&#039;mean&#039;,&#039;std&#039;])\n\u8fd0\u884c\u7ed3\u679c\uff1a\n    mean    std\nkey1        \nx   -0.856065   0.554386\ny   -0.412916   0.214939<\/code><\/pre>\n<p>\u6700\u7ec8\u5f97\u5230\u7684\u5217\u5c31\u4f1a\u4ee5\u76f8\u5e94\u7684\u51fd\u6570\u547d\u540d\u751f\u6210\u4e00\u4e2aDataFrame\u6570\u7ec4<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_gp_3.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_gp_3.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u4ee5\u4e0a\u6211\u4eec\u662f\u53ef\u4ee5\u901a\u8fc7agg\u6216\u8005\u662faggregate\u6765\u5b9e\u73b0\u591a\u51fd\u6570\u805a\u5408\u4ee5\u53ca\u81ea\u5b9a\u4e49\u805a\u5408\u51fd\u6570\uff0c\u4f46\u662f\u4e00\u5b9a\u8981\u6ce8\u610fagg\u65b9\u6cd5\u53ea\u80fd\u8fdb\u884c\u805a\u5408\u64cd\u4f5c\uff0c\u8fdb\u884c\u5176\u4ed6\u4f8b\u5982\uff1a\u6392\u5e8f\uff0c\u8fd9\u4e9b\u65b9\u6cd5\u662f\u4f1a\u62a5\u9519\u7684\u3002agg\u8fd4\u56de\u7684\u662f\u6570\u636e\u7684\u6807\u91cf\uff0c\u6240\u4ee5\u6709\u4e9b\u65f6\u5019\u5e76\u4e0d\u9002\u5408\u4f7f\u7528agg\uff0c\u8fd9\u5c31\u8981\u770b\u6211\u4eec\u63a5\u4e0b\u6765\u7684\u64cd\u4f5c\u4e86\u3002<\/p>\n<h4>3.4.3\u3001apply<\/h4>\n<p>\u200b   GroupBy\u5f53\u4e2d\u81ea\u7531\u5ea6\u6700\u9ad8\u7684\u65b9\u6cd5\u5c31\u662fapply\uff0c\u5b83\u4f1a\u5c06\u5f85\u5904\u7406\u7684\u5bf9\u8c61\u62c6\u5206\u4e3a\u591a\u4e2a\u7247\u6bb5\uff0c\u7136\u540e\u5404\u4e2a\u7247\u6bb5\u5206\u522b\u8c03\u7528\u4f20\u5165\u7684\u51fd\u6570\uff0c\u6700\u540e\u5c06\u5b83\u4eec\u7ec4\u5408\u5230\u4e00\u8d77\u3002<\/p>\n<blockquote>\n<p>df.apply(<br \/>\n[&#8216;func&#8217;, &#8216;axis=0&#8217;, &#8216;broadcast=None&#8217;, &#8216;raw=False&#8217;, &#8216;reduce=None&#8217;, &#8216;result_type=None&#8217;, &#8216;args=()&#8217;, &#8216;**kwds&#8217;]<\/p>\n<\/blockquote>\n<p>func:\u4f20\u5165\u4e00\u4e2a\u81ea\u5b9a\u4e49\u51fd\u6570<br \/>\naxis:\u51fd\u6570\u4f20\u5165\u53c2\u6570\u5f53axis=1\u5c31\u4f1a\u628a\u4e00\u884c\u6570\u636e\u4f5c\u4e3aSeries\u7684\u6570\u636e<\/p>\n<pre><code class=\"language-python\"># \u5206\u6790\u6b27\u6d32\u676f\u548c\u6b27\u6d32\u51a0\u519b\u8054\u8d5b\u51b3\u8d5b\u540d\u5355\nimport pandas as pd\n\nurl=&quot;https:\/\/en.wikipedia.org\/wiki\/List_of_European_Cup_and_UEFA_Champions_League_finals&quot;\neu_champions=pd.read_html(url)  # \u83b7\u53d6\u6570\u636e\na1 = eu_champions[2]    # \u53d6\u51fa\u51b3\u8d5b\u540d\u5355\na1.columns = a1.loc[0]  # \u4f7f\u7528\u7b2c\u4e00\u884c\u7684\u6570\u636e\u66ff\u6362\u9ed8\u8ba4\u7684\u6a2a\u5411\u7d22\u5f15\na1.drop(0,inplace=True)  # \u5c06\u7b2c\u4e00\u884c\u7684\u6570\u636e\u5220\u9664\na1.drop(&#039;#&#039;,axis=1,inplace=True)  # \u5c06\u4ee5#\u4e3a\u5217\u540d\u7684\u90a3\u4e00\u5217\u5220\u9664\na1.columns=[&#039;Season&#039;, &#039;Nation&#039;, &#039;Winners&#039;, &#039;Score&#039;, &#039;Runners_up&#039;, &#039;Runners_up_Nation&#039;, &#039;Venue&#039;,&#039;Attendance&#039;]  # \u8bbe\u7f6e\u5217\u540d\n\na1.tail()  # \u67e5\u770b\u540e\u4e94\u884c\u6570\u636e\na1.drop([64,65],inplace=True)  # \u5220\u9664\u5176\u4e2d\u7684\u7f3a\u5931\u884c\u4ee5\u53ca\u65e0\u7528\u884c\na1<\/code><\/pre>\n<p>\u8fd0\u884c\u7ed3\u679c\uff1a<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/\u5206\u7ec4apply1.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/\u5206\u7ec4apply1.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u73b0\u5728\u60f3\u6839\u636e\u5206\u7ec4\u9009\u51fa<code>Attendance<\/code>\u5217\u4e2d\u503c\u6700\u9ad8\u7684\u4e09\u4e2a\u3002<\/p>\n<pre><code class=\"language-python\"># \u5148\u81ea\u5b9a\u4e49\u4e00\u4e2a\u51fd\u6570\ndef top(df,n=3,column=&#039;Attendance&#039;):\n    return df.sort_values(by=column)[-n:]\ntop(a1,n=3)<\/code><\/pre>\n<p>\u8fd0\u884c\u7ed3\u679c\uff1a<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/\u5206\u7ec4apply2.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/\u5206\u7ec4apply2.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u63a5\u4e0b\u6765\uff0c\u5c31\u5bf9a1\u5206\u7ec4\u5e76\u4e14\u4f7f\u7528apply\u8c03\u7528\u8be5\u51fd\u6570\uff1a<\/p>\n<pre><code class=\"language-python\">a1.groupby(&#039;Nation&#039;).apply(top)<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/\u5206\u7ec4apply3.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/\u5206\u7ec4apply3.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u8fd0\u884c\u4e4b\u540e\u4f1a\u53d1\u73b0\uff0c\u6211\u4eec\u901a\u8fc7\u8fd9\u4e2a\u64cd\u4f5c\u5c06\u6bcf\u4e2a\u56fd\u5bb6\u5404\u4e2a\u5e74\u4efd\u65f6\u6bb5\u51fa\u5e2d\u7684\u4eba\u6570\u7684\u524d\u4e09\u540d\u8fdb\u884c\u4e86\u4e00\u4e2a\u63d0\u53d6\u3002<\/p>\n<p>\u4ee5\u4e0atop\u51fd\u6570\u662f\u5728DataFrame\u7684\u5404\u4e2a\u7247\u6bb5\u4e0a\u8c03\u7528\uff0c\u7136\u540e\u7ed3\u679c\u53c8\u901a\u8fc7pandas.concat\u7ec4\u88c5\u5230\u4e00\u8d77\uff0c\u5e76\u4e14\u4ee5\u5206\u7ec4\u540d\u79f0\u8fdb\u884c\u4e86\u6807\u8bb0\u3002<\/p>\n<p>\u4ee5\u4e0a\u53ea\u662f\u57fa\u672c\u7528\u6cd5\uff0capply\u7684\u5f3a\u5927\u4e4b\u5904\u5c31\u5728\u4e8e\u4f20\u5165\u51fd\u6570\u80fd\u505a\u4ec0\u4e48\u90fd\u7531\u81ea\u5df1\u8bf4\u4e86\u7b97\uff0c\u5b83\u53ea\u662f\u8fd4\u56de\u4e00\u4e2apandas\u5bf9\u8c61\u6216\u8005\u6807\u91cf\u503c\u5c31\u884c<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_gp_4.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/pd_gp_4.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h3>3.5\u3001\u5176\u4ed6\u5e38\u7528\u65b9\u6cd5<\/h3>\n<blockquote>\n<p>pandas\u5e38\u7528\u65b9\u6cd5\uff08\u9002\u7528Series\u548cDataFrame\uff09<\/p>\n<\/blockquote>\n<ul>\n<li>mean(axis=0,skipna=False)<\/li>\n<li>sum(axis=1)<\/li>\n<li>sort_index(axis, \u2026, ascending)        # \u6309\u884c\u6216\u5217\u7d22\u5f15\u6392\u5e8f<\/li>\n<li>sort_values(by, axis, ascending)  # \u6309\u503c\u6392\u5e8f<\/li>\n<li>apply(func, axis=0)   # \u5c06\u81ea\u5b9a\u4e49\u51fd\u6570\u5e94\u7528\u5728\u5404\u884c\u6216\u8005\u5404\u5217\u4e0a\uff0cfunc\u53ef\u8fd4\u56de\u6807\u91cf\u6216\u8005Series<\/li>\n<li>applymap(func)        # \u5c06\u51fd\u6570\u5e94\u7528\u5728DataFrame\u5404\u4e2a\u5143\u7d20\u4e0a<\/li>\n<li>map(func) # \u5c06\u51fd\u6570\u5e94\u7528\u5728Series\u5404\u4e2a\u5143\u7d20\u4e0a<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Pandas \u4ec0\u4e48\u662fPandas pandas\u80fd\u5e72\u4ec0\u4e48 \u600e\u4e48\u7528pandas Series DataFrame  [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[314,310],"tags":[],"_links":{"self":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts\/3630"}],"collection":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3630"}],"version-history":[{"count":0,"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts\/3630\/revisions"}],"wp:attachment":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3630"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3630"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3630"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}