{"id":2075,"date":"2020-09-11T23:03:19","date_gmt":"2020-09-11T14:03:19","guid":{"rendered":"https:\/\/obenkyolab.com\/?p=2075"},"modified":"2021-06-05T23:48:52","modified_gmt":"2021-06-05T14:48:52","slug":"%e3%80%90python%e3%80%91dataframe%e3%81%ae%e4%b8%80%e5%88%97%e3%82%92%e3%81%8d%e3%82%8c%e3%81%84%e3%81%ab%e3%83%aa%e3%82%b9%e3%83%88%e3%81%b8%e5%a4%89%e6%8f%9b%e3%81%99%e3%82%8b","status":"publish","type":"post","link":"https:\/\/obenkyolab.com\/?p=2075","title":{"rendered":"\u3010Python\u3011DataFrame\u306e\u4e00\u5217\u3092\u304d\u308c\u3044\u306b\u30ea\u30b9\u30c8\u3078\u5909\u63db\u3059\u308b"},"content":{"rendered":"\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_80 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/obenkyolab.com\/?p=2075\/#%E6%A6%82%E8%A6%81\" >\u6982\u8981<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/obenkyolab.com\/?p=2075\/#%E3%83%87%E3%83%BC%E3%82%BF%E3%83%99%E3%83%BC%E3%82%B9%E3%81%8B%E3%82%89%E4%B8%80%E5%88%97%E5%8F%96%E5%BE%97%E3%81%99%E3%82%8B%E4%BE%8B\" >\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u4e00\u5217\u53d6\u5f97\u3059\u308b\u4f8b<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/obenkyolab.com\/?p=2075\/#%E4%B8%80%E9%87%8D%E3%83%AA%E3%82%B9%E3%83%88%E3%81%AB%E3%81%99%E3%82%8B\" >\u4e00\u91cd\u30ea\u30b9\u30c8\u306b\u3059\u308b<\/a><\/li><\/ul><\/nav><\/div>\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E6%A6%82%E8%A6%81\"><\/span>\u6982\u8981<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>python\u3067\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u30c7\u30fc\u30bf\u3092\u53d6\u5f97\u3059\u308b\u3068\u304d\u306b\u975e\u5e38\u306b\u4fbf\u5229\u306a\u30e9\u30a4\u30d6\u30e9\u30ea\u3068\u3057\u3066pandas\u304c\u3042\u308a\u307e\u3059\u3002read_sql\u30e1\u30bd\u30c3\u30c9\u3092\u4f7f\u3046\u3068\u3053\u3068\u3067select\u6587\u3092\u4f7f\u7528\u3057\u3066\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089DataFrame\u578b\u3067\u30c7\u30fc\u30bf\u3092\u53d6\u5f97\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u305f\u3060\u3001\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u306e\u30c6\u30fc\u30d6\u30eb\u306e\u3046\u3061\u306e\u4e00\u5217\u3060\u3051\u30ea\u30b9\u30c8\u578b\u3067\u53d6\u5f97\u3057\u305f\u3044\u3068\u304d\u306b\u5c11\u3057\u8e93\u3044\u305f\u306e\u3067\u3001\u5bfe\u51e6\u65b9\u6cd5\u306b\u3064\u3044\u3066\u30e1\u30e2\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E3%83%87%E3%83%BC%E3%82%BF%E3%83%99%E3%83%BC%E3%82%B9%E3%81%8B%E3%82%89%E4%B8%80%E5%88%97%E5%8F%96%E5%BE%97%E3%81%99%E3%82%8B%E4%BE%8B\"><\/span>\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u4e00\u5217\u53d6\u5f97\u3059\u308b\u4f8b<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>\u4f8b\u3048\u3070\u3001\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u5074\uff08PostgreSQL\u3068\u3057\u307e\u3059\uff09\u306b\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u30c6\u30fc\u30d6\u30eb\u304c\u3042\u3063\u305f\u3068\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table><tbody><tr><td>a<\/td><td>b<\/td><td>c<\/td><\/tr><tr><td>1<\/td><td>10<\/td><td>100<\/td><\/tr><tr><td>2<\/td><td>20<\/td><td>200<\/td><\/tr><tr><td>3<\/td><td>30<\/td><td>300<\/td><\/tr><tr><td>4<\/td><td>40<\/td><td>400<\/td><\/tr><\/tbody><\/table><figcaption>test_table<\/figcaption><\/figure>\n\n\n\n<p>\u3053\u306e\u8868\u304b\u3089a\u5217\u3060\u3051\u3092pandas\u3067\u53d6\u308a\u51fa\u3057\u3066\u307f\u307e\u3059\u3002<\/p>\n\n\n<div class=\"wp-block-syntaxhighlighter-code \"><pre class=\"brush: python; title: ; notranslate\" title=\"\">\nimport pandas as pd\nimport psycopg2\n\nconnection = psycopg2.connect(host=&#039;host&#039;, dbname=&#039;database&#039;, user=&#039;username&#039;, password=&#039;password&#039;)\ndf = pd.read_sql(&quot;SELECT a FROM test_table&quot;, connection)\ndf.head()\n<\/pre><\/div>\n\n\n<p>\u7d50\u679c<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"65\" height=\"140\" src=\"https:\/\/obenkyolab.com\/wp-content\/uploads\/2020\/09\/image-7.png\" alt=\"\" class=\"wp-image-2079\"\/><\/figure>\n\n\n\n<p>\u3053\u306ea\u5217\u3092\u30ea\u30b9\u30c8\u306b\u3057\u305f\u3044\u306a\u3041\u3001\u601d\u3063\u305f\u3068\u304d\u3001\u76f4\u611f\u7684\u306b\u306f\u30a4\u30e1\u30fc\u30b8\u3059\u308b\u306e\u306f[1,2,3,4]\u307f\u305f\u3044\u306a\u30ea\u30b9\u30c8\u3060\u3068\u601d\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<p>\u3067\u306f\u3001\u5b9f\u969b\u306b\u3053\u308c\u3092\u30ea\u30b9\u30c8\u5316\u3057\u3066\u307f\u307e\u3059\u3002<\/p>\n\n\n<div class=\"wp-block-syntaxhighlighter-code \"><pre class=\"brush: python; title: ; notranslate\" title=\"\">\ndf.values.tolist()\n\n\u7d50\u679c\n&#x5B;&#x5B;1], &#x5B;2], &#x5B;3], &#x5B;4]]\n<\/pre><\/div>\n\n\n<p>\u4e8c\u91cd\u30ea\u30b9\u30c8\u3067\u51fa\u3066\u304d\u3066\u30a4\u30e1\u30fc\u30b8\u3068\u9055\u3046\u30fb\u30fb\u30fb<\/p>\n\n\n\n<p>\u5f53\u305f\u308a\u524d\u3067\u3059\u304c\u3001\u3044\u304f\u3089select\u6587\u3067\u4e00\u5217\u3060\u3051\u53d6\u308a\u51fa\u3057\u3066\u3082DataFrame\u306fDataFrame\u306a\u306e\u3067\u3001values.tolist()\u3067\u30ea\u30b9\u30c8\u5316\u3057\u3066\u3082\u4e8c\u91cd\u306b\u306a\u3063\u3066\u3057\u307e\u3044\u307e\u3059\u3002\u4eca\u56de\u306f\u3053\u308c\u3092\u4e00\u91cd\u30ea\u30b9\u30c8\u306b\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"%E4%B8%80%E9%87%8D%E3%83%AA%E3%82%B9%E3%83%88%E3%81%AB%E3%81%99%E3%82%8B\"><\/span>\u4e00\u91cd\u30ea\u30b9\u30c8\u306b\u3059\u308b<span class=\"ez-toc-section-end\"><\/span><\/h2>\n\n\n\n<p>itertools\u3092\u4f7f\u3046\u3053\u3068\u3067\u3001\u4ee5\u4e0b\u306e\u30b3\u30fc\u30c9\u3067\u5b9f\u73fe\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n<div class=\"wp-block-syntaxhighlighter-code \"><pre class=\"brush: plain; title: ; notranslate\" title=\"\">\nimport itertools\na = df.values.tolist()\nlist(itertools.chain.from_iterable(a))\n\n\u7d50\u679c\n&#x5B;1, 2, 3, 4]\n<\/pre><\/div>\n\n\n<p>\u975e\u5e38\u306b\u4fbf\u5229\u306a\u306e\u3067\u3001\u4eca\u5f8c\u3082\u4f7f\u7528\u3059\u308b\u6a5f\u4f1a\u304c\u591a\u304f\u306a\u308a\u305d\u3046\u3067\u3059\u3002<\/p>\n\n\n\n<p><\/p>\n\n\n\n<p><strong><span style=\"text-decoration: underline;\">Python\u3092\u4e00\u304b\u3089\u5b66\u3076\u306e\u306b\u304a\u3059\u3059\u3081\u306e\u672c\u306f\u30b3\u30c1\u30e9<\/span><\/strong><\/p>\n\n\n\n<iframe style=\"width:120px;height:240px;\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\" frameborder=\"0\" src=\"https:\/\/rcm-fe.amazon-adsystem.com\/e\/cm?ref=qf_sp_asin_til&#038;t=sebone0f-22&#038;m=amazon&#038;o=9&#038;p=8&#038;l=as1&#038;IS2=1&#038;detail=1&#038;asins=4873117380&#038;linkId=665846163826975f4858844e1483e9e7&#038;bc1=000000&amp;lt1=_blank&#038;fc1=333333&#038;lc1=0066c0&#038;bg1=ffffff&#038;f=ifr\">\n    <\/iframe>\n","protected":false},"excerpt":{"rendered":"<p>\u6982\u8981 python\u3067\u30c7\u30fc\u30bf\u30d9\u30fc\u30b9\u304b\u3089\u30c7\u30fc\u30bf\u3092\u53d6\u5f97\u3059\u308b\u3068\u304d\u306b\u975e\u5e38\u306b\u4fbf\u5229&#46;&#46;&#46;<\/p>\n","protected":false},"author":1,"featured_media":1218,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_locale":"ja","_original_post":"https:\/\/obenkyolab.com\/?p=2075","footnotes":""},"categories":[7],"tags":[],"class_list":["post-2075","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-python","ja"],"_links":{"self":[{"href":"https:\/\/obenkyolab.com\/index.php?rest_route=\/wp\/v2\/posts\/2075","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/obenkyolab.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/obenkyolab.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/obenkyolab.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/obenkyolab.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2075"}],"version-history":[{"count":5,"href":"https:\/\/obenkyolab.com\/index.php?rest_route=\/wp\/v2\/posts\/2075\/revisions"}],"predecessor-version":[{"id":2902,"href":"https:\/\/obenkyolab.com\/index.php?rest_route=\/wp\/v2\/posts\/2075\/revisions\/2902"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/obenkyolab.com\/index.php?rest_route=\/wp\/v2\/media\/1218"}],"wp:attachment":[{"href":"https:\/\/obenkyolab.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2075"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/obenkyolab.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2075"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/obenkyolab.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2075"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}