{"id":6166,"date":"2024-06-26T16:02:49","date_gmt":"2024-06-26T08:02:49","guid":{"rendered":"https:\/\/t.n-years.com\/?p=6166"},"modified":"2024-06-26T16:02:50","modified_gmt":"2024-06-26T08:02:50","slug":"pandas-%e4%b8%bb%e8%a6%81%e6%a6%82%e5%bf%b5%e5%92%8c%e4%b8%bb%e8%a6%81%e5%8a%9f%e8%83%bd%e7%94%a8%e6%b3%95","status":"publish","type":"post","link":"https:\/\/t.n-years.com\/?p=6166","title":{"rendered":"Pandas \u4e3b\u8981\u6982\u5ff5\u548c\u4e3b\u8981\u529f\u80fd\u7528\u6cd5"},"content":{"rendered":"\n<p>Pandas \u662f\u4e00\u4e2a\u7528\u4e8e\u6570\u636e\u64cd\u4f5c\u548c\u5206\u6790\u7684 Python \u5e93\uff0c\u5e7f\u6cdb\u5e94\u7528\u4e8e\u6570\u636e\u79d1\u5b66\u548c\u6570\u636e\u5206\u6790\u9886\u57df\u3002Pandas \u63d0\u4f9b\u4e86\u5f3a\u5927\u7684\u6570\u636e\u7ed3\u6784\u548c\u51fd\u6570\uff0c\u7528\u4e8e\u7b80\u5316\u6570\u636e\u5904\u7406\u4efb\u52a1\u3002\u4ee5\u4e0b\u662f Pandas \u7684\u4e3b\u8981\u6982\u5ff5\u548c\u529f\u80fd\u7528\u6cd5\uff1a<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u4e3b\u8981\u6982\u5ff5<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Series<\/strong>\uff1a<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4e00\u7ef4\u6570\u7ec4\uff0c\u4e0e NumPy \u7684\u4e00\u7ef4\u6570\u7ec4\u7c7b\u4f3c\uff0c\u4f46\u5177\u6709\u8f74\u6807\u7b7e\uff08\u53ef\u4ee5\u662f\u6570\u5b57\u3001\u5b57\u7b26\u4e32\u7b49\uff09\u3002<\/li>\n\n\n\n<li>\u521b\u5efa\uff1a<code>pd.Series(data, index=index)<\/code><\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>   import pandas as pd\n\n   s = pd.Series(&#91;1, 2, 3, 4], index=&#91;'a', 'b', 'c', 'd'])\n   print(s)<\/code><\/pre>\n\n\n\n<ol class=\"wp-block-list\" start=\"2\">\n<li><strong>DataFrame<\/strong>\uff1a<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4e8c\u7ef4\u8868\u683c\u6570\u636e\u7ed3\u6784\uff0c\u6709\u884c\u548c\u5217\u6807\u7b7e\u3002<\/li>\n\n\n\n<li>\u521b\u5efa\uff1a<code>pd.DataFrame(data, index=index, columns=columns)<\/code><\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>   data = {'name': &#91;'Alice', 'Bob', 'Charlie'], 'age': &#91;25, 30, 35]}\n   df = pd.DataFrame(data)\n   print(df)<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u4e3b\u8981\u529f\u80fd\u548c\u7528\u6cd5<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u6570\u636e\u5bfc\u5165\u4e0e\u5bfc\u51fa<\/strong>\uff1a<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4ece CSV \u6587\u4ef6\u5bfc\u5165\uff1a<code>pd.read_csv('file.csv')<\/code><\/li>\n\n\n\n<li>\u5bfc\u51fa\u5230 CSV \u6587\u4ef6\uff1a<code>df.to_csv('file.csv', index=False)<\/code><\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>   df = pd.read_csv('data.csv')\n   df.to_csv('output.csv', index=False)<\/code><\/pre>\n\n\n\n<ol class=\"wp-block-list\" start=\"2\">\n<li><strong>\u6570\u636e\u67e5\u770b\u4e0e\u68c0\u67e5<\/strong>\uff1a<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u67e5\u770b\u524d\u51e0\u884c\uff1a<code>df.head()<\/code><\/li>\n\n\n\n<li>\u67e5\u770b\u6570\u636e\u7ef4\u5ea6\uff1a<code>df.shape<\/code><\/li>\n\n\n\n<li>\u67e5\u770b\u5217\u540d\uff1a<code>df.columns<\/code><\/li>\n\n\n\n<li>\u57fa\u672c\u7edf\u8ba1\u4fe1\u606f\uff1a<code>df.describe()<\/code><\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>   print(df.head())\n   print(df.shape)\n   print(df.columns)\n   print(df.describe())<\/code><\/pre>\n\n\n\n<ol class=\"wp-block-list\" start=\"3\">\n<li><strong>\u6570\u636e\u9009\u62e9\u4e0e\u8fc7\u6ee4<\/strong>\uff1a<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u6309\u5217\u9009\u62e9\uff1a<code>df['column_name']<\/code> \u6216 <code>df.column_name<\/code><\/li>\n\n\n\n<li>\u6309\u884c\u9009\u62e9\uff1a<code>df.loc[index]<\/code>\uff08\u6309\u6807\u7b7e\uff09\u6216 <code>df.iloc[index]<\/code>\uff08\u6309\u4f4d\u7f6e\uff09<\/li>\n\n\n\n<li>\u6761\u4ef6\u7b5b\u9009\uff1a<code>df[df['column_name'] > value]<\/code><\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>   age_series = df&#91;'age']\n   row = df.loc&#91;0]\n   filtered_df = df&#91;df&#91;'age'] &gt; 30]<\/code><\/pre>\n\n\n\n<ol class=\"wp-block-list\" start=\"4\">\n<li><strong>\u6570\u636e\u6e05\u6d17<\/strong>\uff1a<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5904\u7406\u7f3a\u5931\u503c\uff1a<code>df.dropna()<\/code>\uff08\u5220\u9664\u7f3a\u5931\u503c\uff09\u6216 <code>df.fillna(value)<\/code>\uff08\u586b\u5145\u7f3a\u5931\u503c\uff09<\/li>\n\n\n\n<li>\u5220\u9664\u91cd\u590d\u503c\uff1a<code>df.drop_duplicates()<\/code><\/li>\n\n\n\n<li>\u91cd\u547d\u540d\u5217\uff1a<code>df.rename(columns={'old_name': 'new_name'})<\/code><\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>   df_clean = df.dropna()\n   df_clean = df.fillna(0)\n   df_clean = df.drop_duplicates()\n   df_clean = df.rename(columns={'name': 'full_name'})<\/code><\/pre>\n\n\n\n<ol class=\"wp-block-list\" start=\"5\">\n<li><strong>\u6570\u636e\u64cd\u4f5c<\/strong>\uff1a<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u6dfb\u52a0\u65b0\u5217\uff1a<code>df['new_column'] = value<\/code><\/li>\n\n\n\n<li>\u5220\u9664\u5217\uff1a<code>df.drop('column_name', axis=1)<\/code><\/li>\n\n\n\n<li>\u6570\u636e\u5206\u7ec4\uff1a<code>df.groupby('column_name').mean()<\/code><\/li>\n\n\n\n<li>\u6570\u636e\u5408\u5e76\uff1a<code>pd.concat([df1, df2])<\/code> \u6216 <code>pd.merge(df1, df2, on='key_column')<\/code><\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>   df&#91;'new_age'] = df&#91;'age'] + 5\n   df = df.drop('age', axis=1)\n   grouped_df = df.groupby('name').mean()\n   df_merged = pd.merge(df1, df2, on='id')<\/code><\/pre>\n\n\n\n<ol class=\"wp-block-list\" start=\"6\">\n<li><strong>\u6570\u636e\u53ef\u89c6\u5316<\/strong>\uff1a<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4f7f\u7528 Pandas \u5185\u7f6e\u7684\u7ed8\u56fe\u529f\u80fd\uff08\u57fa\u4e8e Matplotlib\uff09\uff1a<code>df.plot()<\/code><\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>   import matplotlib.pyplot as plt\n\n   df&#91;'age'].plot(kind='hist')\n   plt.show()<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u793a\u4f8b\u4ee3\u7801<\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>import pandas as pd\n\n# \u521b\u5efa DataFrame\ndata = {'name': &#91;'Alice', 'Bob', 'Charlie'], 'age': &#91;25, 30, 35]}\ndf = pd.DataFrame(data)\n\n# \u67e5\u770b\u6570\u636e\nprint(df.head())\n\n# \u7b5b\u9009\u6570\u636e\nfiltered_df = df&#91;df&#91;'age'] &gt; 30]\n\n# \u6dfb\u52a0\u65b0\u5217\ndf&#91;'age_next_year'] = df&#91;'age'] + 1\n\n# \u6570\u636e\u5206\u7ec4\ngrouped_df = df.groupby('name').mean()\n\n# \u8f93\u51fa\u5230 CSV \u6587\u4ef6\ndf.to_csv('output.csv', index=False)\n\nprint(filtered_df)\nprint(grouped_df)<\/code><\/pre>\n\n\n\n<p>Pandas \u7684\u8fd9\u4e9b\u529f\u80fd\u4f7f\u5f97\u6570\u636e\u5904\u7406\u548c\u5206\u6790\u66f4\u52a0\u9ad8\u6548\u548c\u7b80\u4fbf\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Pandas \u662f\u4e00\u4e2a\u7528\u4e8e\u6570\u636e\u64cd\u4f5c\u548c\u5206\u6790\u7684 Python \u5e93\uff0c\u5e7f\u6cdb\u5e94\u7528\u4e8e\u6570\u636e\u79d1\u5b66\u548c\u6570\u636e\u5206\u6790\u9886\u57df\u3002Pandas \u63d0&#8230; <\/p>\n<div class=\"read-more navbutton\"><a href=\"https:\/\/t.n-years.com\/?p=6166\">\u9605\u8bfb\u66f4\u591a<i class=\"fa fa-angle-double-right\"><\/i><\/a><\/div>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[5],"tags":[56],"class_list":["post-6166","post","type-post","status-publish","format-standard","hentry","category-5","tag-56"],"_links":{"self":[{"href":"https:\/\/t.n-years.com\/index.php?rest_route=\/wp\/v2\/posts\/6166","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/t.n-years.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/t.n-years.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/t.n-years.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/t.n-years.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=6166"}],"version-history":[{"count":1,"href":"https:\/\/t.n-years.com\/index.php?rest_route=\/wp\/v2\/posts\/6166\/revisions"}],"predecessor-version":[{"id":6167,"href":"https:\/\/t.n-years.com\/index.php?rest_route=\/wp\/v2\/posts\/6166\/revisions\/6167"}],"wp:attachment":[{"href":"https:\/\/t.n-years.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=6166"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/t.n-years.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=6166"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/t.n-years.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=6166"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}