{"id":6055,"date":"2024-05-29T10:04:18","date_gmt":"2024-05-29T02:04:18","guid":{"rendered":"https:\/\/t.n-years.com\/?p=6055"},"modified":"2024-05-29T10:04:19","modified_gmt":"2024-05-29T02:04:19","slug":"pandas-%e6%a1%86%e6%9e%b6%e7%b3%bb%e7%bb%9f%e7%ae%80%e8%a6%81%e4%bb%8b%e7%bb%8d","status":"publish","type":"post","link":"https:\/\/t.n-years.com\/?p=6055","title":{"rendered":"pandas \u6846\u67b6\u7cfb\u7edf\u7b80\u8981\u4ecb\u7ecd"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">\u975e\u539f\u521b\uff0cChatGPT \u95ee\u7b54\u751f\u6210\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Pandas \u662f\u4e00\u4e2a\u5f00\u6e90\u6570\u636e\u5206\u6790\u548c\u6570\u636e\u5904\u7406\u5e93\uff0c\u5e7f\u6cdb\u7528\u4e8e Python \u7f16\u7a0b\u8bed\u8a00\u4e2d\u3002\u5b83\u63d0\u4f9b\u4e86\u6570\u636e\u7ed3\u6784\u548c\u6570\u636e\u5206\u6790\u5de5\u5177\uff0c\u7279\u522b\u9002\u7528\u4e8e\u5904\u7406\u7ed3\u6784\u5316\u6570\u636e\u3002\u4ee5\u4e0b\u662f Pandas \u6846\u67b6\u7684\u4e00\u4e9b\u7b80\u5355\u4ecb\u7ecd\uff0c\u5305\u62ec\u5176\u6838\u5fc3\u6570\u636e\u7ed3\u6784\u3001\u4e3b\u8981\u529f\u80fd\u548c\u5e38\u7528\u64cd\u4f5c\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u6838\u5fc3\u6570\u636e\u7ed3\u6784<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Series<\/strong>:<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4e00\u7ef4\u6570\u636e\u7ed3\u6784\uff0c\u53ef\u4ee5\u5b58\u50a8\u4efb\u4f55\u6570\u636e\u7c7b\u578b\uff08\u6574\u6570\u3001\u6d6e\u70b9\u6570\u3001\u5b57\u7b26\u4e32\u3001Python \u5bf9\u8c61\u7b49\uff09\u3002<\/li>\n\n\n\n<li>\u7c7b\u4f3c\u4e8e Python \u7684\u5217\u8868\u6216\u4e00\u7ef4\u6570\u7ec4\uff0c\u4f46\u5177\u6709\u66f4\u4e30\u5bcc\u7684\u529f\u80fd\u3002<\/li>\n\n\n\n<li>\u5e26\u6709\u7d22\u5f15\u6807\u7b7e\u7684\u6570\u7ec4\uff0c\u7d22\u5f15\u53ef\u4ee5\u662f\u4efb\u610f\u7c7b\u578b\u7684\u6570\u636e\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>   import pandas as pd\n   s = pd.Series(&#91;1, 2, 3, 4, 5], index=&#91;'a', 'b', 'c', 'd', 'e'])\n   print(s)<\/code><\/pre>\n\n\n\n<ol class=\"wp-block-list\" start=\"2\">\n<li><strong>DataFrame<\/strong>:<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4e8c\u7ef4\u6570\u636e\u7ed3\u6784\uff0c\u7c7b\u4f3c\u4e8e\u7535\u5b50\u8868\u683c\u6216 SQL \u8868\u683c\u3002<\/li>\n\n\n\n<li>\u7531\u591a\u4e2a Series \u7ec4\u6210\uff0c\u6bcf\u4e2a Series \u4ee3\u8868\u4e00\u5217\u6570\u636e\u3002<\/li>\n\n\n\n<li>\u5177\u6709\u884c\u7d22\u5f15\u548c\u5217\u7d22\u5f15\uff0c\u53ef\u4ee5\u8fdb\u884c\u5404\u79cd\u6570\u636e\u64cd\u4f5c\uff0c\u5982\u7b5b\u9009\u3001\u6392\u5e8f\u3001\u805a\u5408\u7b49\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>   data = {\n       'name': &#91;'Alice', 'Bob', 'Charlie'],\n       'age': &#91;25, 30, 35],\n       'city': &#91;'New York', 'Los Angeles', 'Chicago']\n   }\n   df = pd.DataFrame(data)\n   print(df)<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u4e3b\u8981\u529f\u80fd<\/h3>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u6570\u636e\u8bfb\u53d6\u4e0e\u5199\u5165<\/strong>:<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u652f\u6301\u591a\u79cd\u683c\u5f0f\u7684\u6570\u636e\u8bfb\u5199\uff0c\u5982 CSV\u3001Excel\u3001SQL\u3001JSON \u7b49\u3002<\/li>\n\n\n\n<li>\u4f8b\u5982\uff0c\u8bfb\u53d6 CSV \u6587\u4ef6\u5e76\u5199\u5165 CSV \u6587\u4ef6\uff1a <code>df = pd.read_csv('file.csv') df.to_csv('output.csv', index=False)<\/code><\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u6570\u636e\u9009\u62e9\u4e0e\u8fc7\u6ee4<\/strong>:<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4f7f\u7528\u6807\u7b7e\u6216\u6761\u4ef6\u8fdb\u884c\u884c\u548c\u5217\u7684\u9009\u62e9\u548c\u8fc7\u6ee4\u3002 <code># \u9009\u62e9\u7279\u5b9a\u7684\u5217 df['name'] # \u9009\u62e9\u7279\u5b9a\u7684\u884c df.loc[0] # \u6761\u4ef6\u8fc7\u6ee4 df[df['age'] > 30]<\/code><\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u6570\u636e\u6e05\u6d17<\/strong>:<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5904\u7406\u7f3a\u5931\u6570\u636e\u3001\u91cd\u590d\u6570\u636e\u3001\u6570\u636e\u8f6c\u6362\u7b49\u64cd\u4f5c\u3002 <code># \u586b\u5145\u7f3a\u5931\u503c df.fillna(0) # \u5220\u9664\u7f3a\u5931\u503c df.dropna() # \u5220\u9664\u91cd\u590d\u503c df.drop_duplicates()<\/code><\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u6570\u636e\u805a\u5408\u4e0e\u5206\u7ec4<\/strong>:<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u6839\u636e\u67d0\u5217\u7684\u503c\u5bf9\u6570\u636e\u8fdb\u884c\u5206\u7ec4\uff0c\u5e76\u8fdb\u884c\u805a\u5408\u64cd\u4f5c\u3002 <code>grouped = df.groupby('city').mean() print(grouped)<\/code><\/li>\n<\/ul>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u6570\u636e\u5408\u5e76<\/strong>:<\/li>\n<\/ol>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5408\u5e76\u591a\u4e2a DataFrame\uff0c\u5982\u8fde\u63a5\uff08join\uff09\u548c\u62fc\u63a5\uff08concat\uff09\u3002 <code>df1 = pd.DataFrame({'key': ['A', 'B', 'C'], 'value1': [1, 2, 3]}) df2 = pd.DataFrame({'key': ['A', 'B', 'D'], 'value2': [4, 5, 6]}) # \u6309\u952e\u8fde\u63a5 merged = pd.merge(df1, df2, on='key') print(merged) # \u62fc\u63a5 concatenated = pd.concat([df1, df2], ignore_index=True) print(concatenated)<\/code><\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\u793a\u4f8b\uff1a\u8bfb\u53d6\u3001\u5904\u7406\u5e76\u5408\u5e76\u4e24\u4e2a CSV \u6587\u4ef6\u4e2d\u7684\u7279\u5b9a\u5217<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u5047\u8bbe\u6709\u4e24\u4e2a CSV \u6587\u4ef6 <code>file1.csv<\/code> \u548c <code>file2.csv<\/code>\uff0c\u6bcf\u4e2a\u6587\u4ef6\u90fd\u6709 <code>category<\/code> \u548c <code>text<\/code> \u5217\uff0c\u6211\u4eec\u5c06\u5b83\u4eec\u8bfb\u53d6\u5e76\u5408\u5e76\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>import pandas as pd\n\n# \u8bfb\u53d6\u6587\u4ef6\u5e76\u67e5\u770b\u5217\u540d\ndf1 = pd.read_csv('file1.csv')\ndf2 = pd.read_csv('file2.csv')\nprint(df1.columns)\nprint(df2.columns)\n\n# \u5982\u679c\u5217\u540d\u6709\u95ee\u9898\uff0c\u53ef\u4ee5\u624b\u52a8\u8c03\u6574\u6216\u4f7f\u7528\u5217\u7d22\u5f15\ndf1 = pd.read_csv('file1.csv', usecols=&#91;'category', 'text'])\ndf2 = pd.read_csv('file2.csv', usecols=&#91;'category', 'text'])\n\n# \u5408\u5e76\u4e24\u4e2aDataFrame\nmerged_df = pd.concat(&#91;df1, df2], ignore_index=True)\n\n# \u5199\u5165\u65b0\u7684CSV\u6587\u4ef6\nmerged_df.to_csv('merged.csv', index=False)\n\nprint(merged_df)<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u603b\u7ed3<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Pandas \u63d0\u4f9b\u4e86\u5f3a\u5927\u7684\u6570\u636e\u64cd\u4f5c\u529f\u80fd\uff0c\u53ef\u4ee5\u8f7b\u677e\u8bfb\u53d6\u3001\u5904\u7406\u548c\u5206\u6790\u6570\u636e\u3002\u901a\u8fc7\u5b66\u4e60\u548c\u638c\u63e1 Pandas \u7684\u57fa\u672c\u64cd\u4f5c\uff0c\u53ef\u4ee5\u5927\u5927\u63d0\u9ad8\u6570\u636e\u5206\u6790\u7684\u6548\u7387\u548c\u51c6\u786e\u6027\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u975e\u539f\u521b\uff0cChatGPT \u95ee\u7b54\u751f\u6210\u3002 Pandas \u662f\u4e00\u4e2a\u5f00\u6e90\u6570\u636e\u5206\u6790\u548c\u6570\u636e\u5904\u7406\u5e93\uff0c\u5e7f\u6cdb\u7528\u4e8e Python \u7f16\u7a0b&#8230; <\/p>\n<div class=\"read-more navbutton\"><a href=\"https:\/\/t.n-years.com\/?p=6055\">\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":[56,51],"class_list":["post-6055","post","type-post","status-publish","format-standard","hentry","category-5","tag-56","tag-51"],"_links":{"self":[{"href":"https:\/\/t.n-years.com\/index.php?rest_route=\/wp\/v2\/posts\/6055","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=6055"}],"version-history":[{"count":1,"href":"https:\/\/t.n-years.com\/index.php?rest_route=\/wp\/v2\/posts\/6055\/revisions"}],"predecessor-version":[{"id":6056,"href":"https:\/\/t.n-years.com\/index.php?rest_route=\/wp\/v2\/posts\/6055\/revisions\/6056"}],"wp:attachment":[{"href":"https:\/\/t.n-years.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=6055"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/t.n-years.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=6055"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/t.n-years.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=6055"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}