{"id":3461,"date":"2024-02-08T06:24:16","date_gmt":"2024-02-07T21:24:16","guid":{"rendered":"https:\/\/www.dogrow.net\/python\/?p=3461"},"modified":"2024-02-08T06:34:21","modified_gmt":"2024-02-07T21:34:21","slug":"blog121","status":"publish","type":"post","link":"https:\/\/www.dogrow.net\/python\/blog121\/","title":{"rendered":"(121) Pandas\u3067\u306fCSV\u30d5\u30a1\u30a4\u30eb\u306e\u672a\u5165\u529b\u30bb\u30eb\u3092NaN\u3068\u3059\u308b\u3002"},"content":{"rendered":"<h1 class=\"my_h\">\u30101\u3011\u554f\u984c\u767a\u751f<\/h1>\n<p>\u524d\u6295\u7a3f <a href=\"https:\/\/www.dogrow.net\/python\/blog120\/\" target=\"_blank\" rel=\"noopener\">(120) Pandas\u3067CSV\u30d5\u30a1\u30a4\u30eb\u306e\u4e2d\u8eab\u3092\u5909\u66f4\u3057\u3066CSV\u30d5\u30a1\u30a4\u30eb\u306b\u4fdd\u5b58<\/a> \u3067\u306f\u3001\u30ed\u30fc\u30c9\u3057\u305f CSV\u30d5\u30a1\u30a4\u30eb\u306e\u4e2d\u8eab\u3092\u66f8\u304d\u63db\u3048\u308b\u7df4\u7fd2\u3092\u3057\u305f\u3002<br \/>\n\u3053\u306e\u6642\u306b\u8a66\u3057\u305f CSV\u30d5\u30a1\u30a4\u30eb\u306e\u4e2d\u306b\u3001\u30bb\u30eb\u306e\u5024\u304c\u672a\u5165\u529b\u306e\u7269\u304c\u3042\u308a\u3001\u4ee5\u4e0b\u306e\u30a8\u30e9\u30fc\u304c\u767a\u751f\u3057\u305f\u3002<\/p>\n<pre class=\"my_pre\">\r\n>>> df['\u4f4f\u6240'] = df['\u4f4f\u6240'].apply(lambda x: re.sub(r'\\d.*', '', x))\r\nTraceback (most recent call last):\r\n  File \"<stdin>\", line 1, in <module>\r\n  File \"Python312\/site-packages\/pandas\/core\/series.py\", line 4904, in apply\r\n    ).apply()\r\n      ^^^^^^^\r\n  File \"Python312\/site-packages\/pandas\/core\/apply.py\", line 1427, in apply\r\n    return self.apply_standard()\r\n           ^^^^^^^^^^^^^^^^^^^^^\r\n  File \"Python312\/site-packages\/pandas\/core\/apply.py\", line 1507, in apply_standard\r\n    mapped = obj._map_values(\r\n             ^^^^^^^^^^^^^^^^\r\n  File \"Python312\/site-packages\/pandas\/core\/base.py\", line 921, in _map_values\r\n    return algorithms.map_array(arr, mapper, na_action=na_action, convert=convert)\r\n           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\r\n  File \"Python312\/site-packages\/pandas\/core\/algorithms.py\", line 1743, in map_array\r\n    return lib.map_infer(values, mapper, convert=convert)\r\n           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\r\n  File \"lib.pyx\", line 2972, in pandas._libs.lib.map_infer\r\n  File \"<stdin>\", line 1, in <lambda>\r\n  File \"__init__.py\", line 186, in sub\r\n    return _compile(pattern, flags).sub(repl, string, count)\r\n           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\r\n<span class=\"my_fc_redB\">TypeError: expected string or bytes-like object, got 'float'<\/span>\r\n<\/pre>\n<p><span class=\"my_fc_redBBig\">\u3093\uff1f<br \/>\nCSV\u30d5\u30a1\u30a4\u30eb\u306e\u30c7\u30fc\u30bf\u306e\u4e2d\u306b float\u5024\u306a\u3093\u304b\u5165\u3063\u3066\u306a\u3044\u305e\uff1f<\/span><\/p>\n<h1 class=\"my_h\">\u30102\u3011\u539f\u56e0<\/h1>\n<p>CSV\u30d5\u30a1\u30a4\u30eb\u306e\u4e2d\u306b\u3001<span class=\"my_fc_redBBig\">\u7a7a\u767d\u30bb\u30eb<\/span> \u304c\u542b\u307e\u308c\u3066\u3044\u305f\u3002<\/p>\n<p>\u3053\u306e CSV\u30d5\u30a1\u30a4\u30eb\u3092 <span class=\"my_fc_deeppinkB\">pandas.read_csv()<\/span> \u3067\u8aad\u307f\u51fa\u3057\u305f\u6642\u306b\u3001<br \/>\n<span class=\"my_fc_redBBig\">\u7a7a\u767d\u30bb\u30eb\u306e\u5024\u304c NAN (Not a Number)\u3068\u3057\u3066\u8a8d\u8b58<\/span> \u3055\u308c\u3066\u3044\u305f\u3002<br \/>\nPandas\u3067\u306f\u3001\u305d\u3046\u3044\u3046\u4ed5\u69d8\u3089\u3057\u3044\u3002<\/p>\n<h1 class=\"my_h\">\u30103\u3011\u5bfe\u5fdc\u7b56<\/h1>\n<p>\u30d7\u30ed\u30b0\u30e9\u30e0\u306e\u8a72\u5f53\u7b87\u6240\u3092\u4ee5\u4e0b\u306e\u3088\u3046\u306b\u66f8\u304d\u63db\u3048\u3066\u5bfe\u5fdc\u3059\u308b\u3053\u3068\u306b\u3057\u305f\u3002<br \/>\n<span class=\"my_fc_blueBBig\">\u30bb\u30eb\u306e\u5024\u304c\u6587\u5b57\u5217\u578b\u304b\uff1f <\/span><br \/>\n\u3092 <span class=\"my_fc_deeppinkB\">if isinstance(x, str)<\/span> \u3067\u30c1\u30a7\u30c3\u30af\u3057\u305f\u5f8c\u306b <span class=\"my_fc_deeppinkB\">re.sub()<\/span> \u3092\u5b9f\u884c\u3059\u308b\u3088\u3046\u306b\u3057\u305f\u3002<\/p>\n<p><span class=\"my_fc_redBBig\">before<\/span><\/p>\n<pre class=\"brush: python; title: ; notranslate\" title=\"\">\r\ndf&#x5B;2] = df&#x5B;2].apply(lambda x: re.sub(r'\\d.*', '', x))\r\n<\/pre>\n<p><span class=\"my_fc_blueBBig\">after<\/span><\/p>\n<pre class=\"brush: python; title: ; notranslate\" title=\"\">\r\ndf&#x5B;2] = df&#x5B;2].apply(lambda x: re.sub(r'\\d.*', '', x) if isinstance(x, str) else x)\r\n<\/pre>\n<h1 class=\"my_h\">\u30104\u3011\u88dc\u8db3\u60c5\u5831<\/h1>\n<p>ChatGPT\u5927\u5148\u751f\u304b\u3089\u4ee5\u4e0b\u306e\u8b39\u8a00\u3092\u8cdc\u3063\u305f\u3002<\/p>\n<pre class=\"my_pre\">\r\nCSV\u30d5\u30a1\u30a4\u30eb\u5185\u3067\u3001\u4f55\u3089\u304b\u306e\u30bb\u30eb\u304c\u672a\u5165\u529b\uff08\u7a7a\u767d\uff09\u3067\u3042\u308b\u5834\u5408\u3001Pandas\u306f\u305d\u306e\u30bb\u30eb\u3092NaN\u3068\u3057\u3066DataFrame\u5185\u306b\u8aad\u307f\u8fbc\u307f\u307e\u3059\u3002\r\n\r\n\u6b20\u640d\u5024\u306e\u6271\u3044\r\nPandas\u3067\u306f\u3001NaN\u5024\u3092\u6271\u3046\u305f\u3081\u306e\u3044\u304f\u3064\u304b\u306e\u4fbf\u5229\u306a\u30e1\u30bd\u30c3\u30c9\u304c\u3042\u308a\u307e\u3059\u3002\r\n\r\n\u4f8b\u3048\u3070\uff1a\r\nisna()\u307e\u305f\u306fisnull()\u3092\u4f7f\u7528\u3057\u3066\u3001\u30c7\u30fc\u30bf\u30d5\u30ec\u30fc\u30e0\u5185\u306eNaN\u5024\u3092\u691c\u51fa\u3059\u308b\u3002\r\nfillna()\u3092\u4f7f\u7528\u3057\u3066\u3001NaN\u5024\u3092\u7279\u5b9a\u306e\u5024\u3084\u65b9\u6cd5\uff08\u524d\u306e\u5024\u3084\u6b21\u306e\u5024\u3067\u57cb\u3081\u308b\u306a\u3069\uff09\u3067\u7f6e\u304d\u63db\u3048\u308b\u3002\r\ndropna()\u3092\u4f7f\u7528\u3057\u3066\u3001NaN\u5024\u3092\u542b\u3080\u884c\u3084\u5217\u3092\u524a\u9664\u3059\u308b\u3002\r\n\r\n\u6ce8\u610f\u70b9\r\nPandas\u306f\u30c7\u30d5\u30a9\u30eb\u30c8\u3067\u7a7a\u767d\u306e\u30bb\u30eb\u3092NaN\u3068\u3057\u3066\u6271\u3044\u307e\u3059\u304c\u3001read_csv\u95a2\u6570\u306ena_values\u30d1\u30e9\u30e1\u30fc\u30bf\u3092\u4f7f\u7528\u3057\u3066\u3001NaN\u3068\u3057\u3066\u8a8d\u8b58\u3055\u305b\u305f\u3044\u4ed6\u306e\u5024\uff08\u4f8b\u3048\u3070\u7279\u5b9a\u306e\u6587\u5b57\u5217\u3084\u8a18\u53f7\uff09\u3092\u6307\u5b9a\u3059\u308b\u3053\u3068\u3082\u3067\u304d\u307e\u3059\u3002\r\n\r\n\u307e\u305f\u3001\u6570\u5024\u30c7\u30fc\u30bf\u306e\u5217\u3067NaN\u304c\u4f7f\u7528\u3055\u308c\u308b\u5834\u5408\u3001\u305d\u306e\u5217\u306f\u6d6e\u52d5\u5c0f\u6570\u70b9\u578b\u306b\u81ea\u52d5\u7684\u306b\u5909\u63db\u3055\u308c\u307e\u3059\u3002\r\n\u3053\u308c\u306f\u3001Pandas\u304c\u6574\u6570\u578b\u306e\u5217\u306bNaN\u5024\u3092\u683c\u7d0d\u3059\u308b\u3053\u3068\u304c\u3067\u304d\u306a\u3044\u305f\u3081\u3067\u3059\uff08Pandas\u306e\u30d0\u30fc\u30b8\u30e7\u30f3\u306b\u3088\u3063\u3066\u306f\u3001\u6574\u6570\u578b\u306eNA\u5024\u3092\u6271\u3046\u65b0\u3057\u3044\u30c7\u30fc\u30bf\u578b\u304c\u5c0e\u5165\u3055\u308c\u3066\u3044\u308b\u5834\u5408\u304c\u3042\u308a\u307e\u3059\uff09\u3002\r\n<\/pre>\n<hr class=\"my_hr_bottom\">\n","protected":false},"excerpt":{"rendered":"<p>\u30101\u3011\u554f\u984c\u767a\u751f \u524d\u6295\u7a3f (120) Pandas\u3067CSV\u30d5\u30a1\u30a4\u30eb\u306e\u4e2d\u8eab\u3092\u5909\u66f4\u3057\u3066CSV\u30d5\u30a1\u30a4\u30eb\u306b\u4fdd\u5b58 \u3067\u306f\u3001\u30ed\u30fc\u30c9\u3057\u305f CSV\u30d5\u30a1\u30a4\u30eb\u306e\u4e2d\u8eab\u3092\u66f8\u304d\u63db\u3048\u308b\u7df4\u7fd2\u3092\u3057\u305f\u3002 \u3053\u306e\u6642\u306b\u8a66\u3057\u305f CSV\u30d5\u30a1\u30a4\u30eb\u306e\u4e2d\u306b\u3001\u30bb\u30eb\u306e\u5024\u304c\u672a\u5165\u529b\u2026 <span class=\"read-more\"><a href=\"https:\/\/www.dogrow.net\/python\/blog121\/\">\u7d9a\u304d\u3092\u8aad\u3080 &raquo;<\/a><\/span><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[55,42],"tags":[],"class_list":["post-3461","post","type-post","status-publish","format-standard","hentry","category-csv","category-pandas"],"views":993,"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/www.dogrow.net\/python\/wp-json\/wp\/v2\/posts\/3461","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.dogrow.net\/python\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.dogrow.net\/python\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.dogrow.net\/python\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.dogrow.net\/python\/wp-json\/wp\/v2\/comments?post=3461"}],"version-history":[{"count":12,"href":"https:\/\/www.dogrow.net\/python\/wp-json\/wp\/v2\/posts\/3461\/revisions"}],"predecessor-version":[{"id":3473,"href":"https:\/\/www.dogrow.net\/python\/wp-json\/wp\/v2\/posts\/3461\/revisions\/3473"}],"wp:attachment":[{"href":"https:\/\/www.dogrow.net\/python\/wp-json\/wp\/v2\/media?parent=3461"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.dogrow.net\/python\/wp-json\/wp\/v2\/categories?post=3461"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.dogrow.net\/python\/wp-json\/wp\/v2\/tags?post=3461"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}