{"id":1080084,"date":"2025-01-08T12:26:49","date_gmt":"2025-01-08T04:26:49","guid":{"rendered":"https:\/\/docs.pingcode.com\/ask\/ask-ask\/1080084.html"},"modified":"2025-01-08T12:26:51","modified_gmt":"2025-01-08T04:26:51","slug":"python%e5%a6%82%e4%bd%95%e6%89%be%e5%88%b0list%e4%b8%ad%e5%85%83%e7%b4%a0%e7%9a%84%e4%bd%8d%e7%bd%ae-2","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/1080084.html","title":{"rendered":"python\u5982\u4f55\u627e\u5230list\u4e2d\u5143\u7d20\u7684\u4f4d\u7f6e"},"content":{"rendered":"

\"python\u5982\u4f55\u627e\u5230list\u4e2d\u5143\u7d20\u7684\u4f4d\u7f6e\"<\/p>\n

\u5728 Python \u4e2d\u627e\u5230\u5217\u8868\uff08list\uff09\u4e2d\u5143\u7d20\u7684\u4f4d\u7f6e\u6709\u591a\u79cd\u65b9\u6cd5\uff0c\u5305\u62ec\u4f7f\u7528\u5185\u7f6e\u51fd\u6570\u3001\u5217\u8868\u63a8\u5bfc\u5f0f\u548c\u5916\u90e8\u5e93\u3002\u6700\u5e38\u7528\u7684\u65b9\u6cd5\u662f\u4f7f\u7528 index()<\/code> \u65b9\u6cd5\uff0c\u4f46\u8fd8\u6709\u5176\u4ed6\u6709\u6548\u7684\u65b9\u6cd5\uff0c\u5982\u904d\u5386\u5217\u8868\u3001\u4f7f\u7528 numpy \u5e93\u7b49\u3002<\/strong> \u4e0b\u9762\u5c06\u8be6\u7ec6\u4ecb\u7ecd\u8fd9\u4e9b\u65b9\u6cd5\uff0c\u5e76\u6df1\u5165\u63a2\u8ba8\u6bcf\u79cd\u65b9\u6cd5\u7684\u4f18\u7f3a\u70b9\u548c\u9002\u7528\u573a\u666f\u3002<\/p>\n<\/p>\n

\u4e00\u3001\u4f7f\u7528 index()<\/code> \u65b9\u6cd5<\/p>\n<\/p>\n

Python \u63d0\u4f9b\u4e86\u4e00\u4e2a\u5185\u7f6e\u65b9\u6cd5 index()<\/code>\uff0c\u5b83\u53ef\u4ee5\u76f4\u63a5\u7528\u4e8e\u67e5\u627e\u5217\u8868\u4e2d\u5143\u7d20\u7684\u4f4d\u7f6e\u3002\u8fd9\u4e2a\u65b9\u6cd5\u5728\u67e5\u627e\u5143\u7d20\u65f6\u6548\u7387\u8f83\u9ad8\uff0c\u4e14\u4ee3\u7801\u7b80\u5355\u6613\u8bfb\u3002<\/p>\n<\/p>\n

my_list = [1, 2, 3, 4, 5]<\/p>\n
position = my_list.index(3)<\/p>\n
print("Element 3 is at position:", position)<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u4f18\u70b9\uff1a<\/strong><\/p>\n<\/p>\n
    \n
  1. \u7b80\u5355\u660e\u4e86<\/strong>\uff1aindex()<\/code> \u65b9\u6cd5\u6613\u4e8e\u7406\u89e3\u548c\u4f7f\u7528\u3002<\/li>\n
  2. \u9ad8\u6548<\/strong>\uff1a\u5bf9\u4e8e\u5c0f\u578b\u5217\u8868\uff0cindex()<\/code> \u65b9\u6cd5\u6027\u80fd\u826f\u597d\u3002<\/li>\n<\/ol>\n
    \u7f3a\u70b9\uff1a<\/strong><\/p>\n<\/p>\n
      \n
    1. \u4ec5\u627e\u5230\u7b2c\u4e00\u4e2a\u5339\u914d\u9879<\/strong>\uff1a\u5982\u679c\u5217\u8868\u4e2d\u6709\u591a\u4e2a\u76f8\u540c\u7684\u5143\u7d20\uff0cindex()<\/code> \u53ea\u80fd\u8fd4\u56de\u7b2c\u4e00\u4e2a\u5339\u914d\u9879\u7684\u4f4d\u7f6e\u3002<\/li>\n
    2. \u62a5\u9519<\/strong>\uff1a\u5982\u679c\u5143\u7d20\u4e0d\u5b58\u5728\uff0cindex()<\/code> \u4f1a\u629b\u51fa ValueError<\/code> \u5f02\u5e38\uff0c\u9700\u8981\u989d\u5916\u5904\u7406\u3002<\/li>\n<\/ol>\n
      \u4e8c\u3001\u904d\u5386\u5217\u8868<\/p>\n<\/p>\n
      \u901a\u8fc7\u904d\u5386\u5217\u8868\uff0c\u53ef\u4ee5\u627e\u5230\u6240\u6709\u5339\u914d\u5143\u7d20\u7684\u4f4d\u7f6e\u3002\u8fd9\u79cd\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u67e5\u627e\u6240\u6709\u5339\u914d\u4f4d\u7f6e\u7684\u60c5\u51b5\u3002<\/p>\n<\/p>\n
      my_list = [1, 2, 3, 2, 4, 2]<\/p>\n
      positions = [index for index, value in enumerate(my_list) if value == 2]<\/p>\n
      print("Element 2 is at positions:", positions)<\/p>\n
      <\/code><\/pre>\n<\/p>\n
      \u4f18\u70b9\uff1a<\/strong><\/p>\n<\/p>\n
        \n
      1. \u627e\u5230\u6240\u6709\u5339\u914d\u9879<\/strong>\uff1a\u53ef\u4ee5\u627e\u5230\u6240\u6709\u5339\u914d\u5143\u7d20\u7684\u4f4d\u7f6e\u3002<\/li>\n
      2. \u7075\u6d3b\u6027\u9ad8<\/strong>\uff1a\u53ef\u4ee5\u6dfb\u52a0\u989d\u5916\u7684\u6761\u4ef6\u8fc7\u6ee4\u3002<\/li>\n<\/ol>\n
        \u7f3a\u70b9\uff1a<\/strong><\/p>\n<\/p>\n
          \n
        1. \u6548\u7387\u8f83\u4f4e<\/strong>\uff1a\u5bf9\u5927\u578b\u5217\u8868\u6027\u80fd\u8f83\u5dee\uff0c\u65f6\u95f4\u590d\u6742\u5ea6\u4e3a O(n)\u3002<\/li>\n<\/ol>\n
          \u4e09\u3001\u4f7f\u7528 numpy \u5e93<\/p>\n<\/p>\n
          \u5bf9\u4e8e\u5927\u578b\u6570\u7ec4\u6216\u9700\u8981\u9ad8\u6548\u8ba1\u7b97\u7684\u573a\u666f\uff0c\u53ef\u4ee5\u4f7f\u7528 numpy<\/code> \u5e93\u3002numpy<\/code> \u63d0\u4f9b\u4e86\u9ad8\u6548\u7684\u6570\u7ec4\u5904\u7406\u529f\u80fd\u3002<\/p>\n<\/p>\n
          import numpy as np<\/p>\n
          my_array = np.array([1, 2, 3, 2, 4, 2])<\/p>\n
          positions = np.where(my_array == 2)[0]<\/p>\n
          print("Element 2 is at positions:", positions)<\/p>\n
          <\/code><\/pre>\n<\/p>\n
          \u4f18\u70b9\uff1a<\/strong><\/p>\n<\/p>\n
            \n
          1. \u9ad8\u6548<\/strong>\uff1anumpy<\/code> \u5728\u5904\u7406\u5927\u578b\u6570\u7ec4\u65f6\u6027\u80fd\u4f18\u8d8a\u3002<\/li>\n
          2. \u7b80\u6d01<\/strong>\uff1a\u4ee3\u7801\u7b80\u6d01\u6613\u8bfb\u3002<\/li>\n<\/ol>\n
            \u7f3a\u70b9\uff1a<\/strong><\/p>\n<\/p>\n
              \n
            1. \u5916\u90e8\u4f9d\u8d56<\/strong>\uff1a\u9700\u8981\u5b89\u88c5 numpy<\/code> \u5e93\u3002<\/li>\n
            2. \u4e0d\u9002\u7528\u4e8e\u5c0f\u578b\u5217\u8868<\/strong>\uff1a\u5bf9\u4e8e\u5c0f\u578b\u5217\u8868\uff0c\u4f7f\u7528 numpy<\/code> \u53ef\u80fd\u663e\u5f97\u8fc7\u4e8e\u590d\u6742\u3002<\/li>\n<\/ol>\n
              \u56db\u3001\u4f7f\u7528 pandas \u5e93<\/p>\n<\/p>\n
              pandas<\/code> \u5e93\u4e5f\u662f\u4e00\u79cd\u9ad8\u6548\u5904\u7406\u6570\u636e\u7684\u5de5\u5177\uff0c\u5c24\u5176\u9002\u7528\u4e8e\u6570\u636e\u5206\u6790\u548c\u5904\u7406\u573a\u666f\u3002<\/p>\n<\/p>\n
              import pandas as pd<\/p>\n
              my_series = pd.Series([1, 2, 3, 2, 4, 2])<\/p>\n
              positions = my_series[my_series == 2].index.tolist()<\/p>\n
              print("Element 2 is at positions:", positions)<\/p>\n
              <\/code><\/pre>\n<\/p>\n
              \u4f18\u70b9\uff1a<\/strong><\/p>\n<\/p>\n
                \n
              1. \u9ad8\u6548<\/strong>\uff1apandas<\/code> \u5728\u5904\u7406\u5927\u578b\u6570\u636e\u96c6\u65f6\u6027\u80fd\u4f18\u8d8a\u3002<\/li>\n
              2. \u5f3a\u5927\u7684\u6570\u636e\u5904\u7406\u529f\u80fd<\/strong>\uff1a\u9002\u7528\u4e8e\u590d\u6742\u6570\u636e\u5206\u6790\u573a\u666f\u3002<\/li>\n<\/ol>\n
                \u7f3a\u70b9\uff1a<\/strong><\/p>\n<\/p>\n
                  \n
                1. \u5916\u90e8\u4f9d\u8d56<\/strong>\uff1a\u9700\u8981\u5b89\u88c5 pandas<\/code> \u5e93\u3002<\/li>\n
                2. \u5b66\u4e60\u6210\u672c\u8f83\u9ad8<\/strong>\uff1apandas<\/code> \u529f\u80fd\u4e30\u5bcc\uff0c\u9700\u8981\u4e00\u5b9a\u7684\u5b66\u4e60\u6210\u672c\u3002<\/li>\n<\/ol>\n
                  \u4e94\u3001\u4f7f\u7528\u81ea\u5b9a\u4e49\u51fd\u6570<\/p>\n<\/p>\n
                  \u53ef\u4ee5\u7f16\u5199\u81ea\u5b9a\u4e49\u51fd\u6570\u6765\u67e5\u627e\u5217\u8868\u4e2d\u5143\u7d20\u7684\u4f4d\u7f6e\uff0c\u4ee5\u6ee1\u8db3\u7279\u5b9a\u9700\u6c42\u3002<\/p>\n<\/p>\n
                  def find_positions(lst, element):<\/p>\n
                      return [index for index, value in enumerate(lst) if value == element]<\/p>\n
                  my_list = [1, 2, 3, 2, 4, 2]<\/p>\n
                  positions = find_positions(my_list, 2)<\/p>\n
                  print("Element 2 is at positions:", positions)<\/p>\n
                  <\/code><\/pre>\n<\/p>\n
                  \u4f18\u70b9\uff1a<\/strong><\/p>\n<\/p>\n
                    \n
                  1. \u7075\u6d3b\u6027\u9ad8<\/strong>\uff1a\u53ef\u4ee5\u6839\u636e\u9700\u6c42\u81ea\u5b9a\u4e49\u67e5\u627e\u903b\u8f91\u3002<\/li>\n
                  2. \u53ef\u6269\u5c55\u6027\u5f3a<\/strong>\uff1a\u53ef\u4ee5\u6dfb\u52a0\u989d\u5916\u7684\u529f\u80fd\uff0c\u5982\u6761\u4ef6\u8fc7\u6ee4\u3001\u5904\u7406\u5f02\u5e38\u7b49\u3002<\/li>\n<\/ol>\n
                    \u7f3a\u70b9\uff1a<\/strong><\/p>\n<\/p>\n
                      \n
                    1. \u6548\u7387\u8f83\u4f4e<\/strong>\uff1a\u81ea\u5b9a\u4e49\u51fd\u6570\u7684\u6548\u7387\u53ef\u80fd\u4e0d\u5982\u5185\u7f6e\u65b9\u6cd5\u548c\u5916\u90e8\u5e93\u3002<\/li>\n
                    2. \u4ee3\u7801\u590d\u6742\u5ea6\u9ad8<\/strong>\uff1a\u4ee3\u7801\u53ef\u80fd\u8f83\u4e3a\u590d\u6742\uff0c\u589e\u52a0\u7ef4\u62a4\u6210\u672c\u3002<\/li>\n<\/ol>\n
                      \u516d\u3001\u603b\u7ed3<\/p>\n<\/p>\n
                      \u5728 Python \u4e2d\u627e\u5230\u5217\u8868\u4e2d\u5143\u7d20\u7684\u4f4d\u7f6e\u6709\u591a\u79cd\u65b9\u6cd5\uff0c\u6bcf\u79cd\u65b9\u6cd5\u90fd\u6709\u5176\u4f18\u7f3a\u70b9\u548c\u9002\u7528\u573a\u666f\u3002\u9009\u62e9\u5408\u9002\u7684\u65b9\u6cd5\u53d6\u51b3\u4e8e\u5177\u4f53\u9700\u6c42\u548c\u573a\u666f\uff1a<\/p>\n<\/p>\n
                        \n
                      1. \u5c0f\u578b\u5217\u8868<\/strong>\uff1a\u4f7f\u7528 index()<\/code> \u65b9\u6cd5\u7b80\u5355\u9ad8\u6548\u3002<\/li>\n
                      2. \u67e5\u627e\u6240\u6709\u5339\u914d\u9879<\/strong>\uff1a\u4f7f\u7528\u904d\u5386\u5217\u8868\u6216\u81ea\u5b9a\u4e49\u51fd\u6570\u3002<\/li>\n
                      3. \u5927\u578b\u6570\u7ec4<\/strong>\uff1a\u4f7f\u7528 numpy<\/code> \u5e93\u9ad8\u6548\u5904\u7406\u3002<\/li>\n
                      4. \u6570\u636e\u5206\u6790<\/strong>\uff1a\u4f7f\u7528 pandas<\/code> \u5e93\u5f3a\u5927\u7684\u6570\u636e\u5904\u7406\u529f\u80fd\u3002<\/li>\n<\/ol>\n
                        \u901a\u8fc7\u4e86\u89e3\u548c\u638c\u63e1\u8fd9\u4e9b\u65b9\u6cd5\uff0c\u53ef\u4ee5\u5728\u4e0d\u540c\u573a\u666f\u4e0b\u7075\u6d3b\u9009\u62e9\u6700\u5408\u9002\u7684\u89e3\u51b3\u65b9\u6848\uff0c\u63d0\u9ad8\u4ee3\u7801\u7684\u6548\u7387\u548c\u53ef\u8bfb\u6027\u3002\u5e0c\u671b\u8fd9\u7bc7\u6587\u7ae0\u80fd\u5e2e\u52a9\u4f60\u66f4\u597d\u5730\u7406\u89e3\u548c\u5e94\u7528 Python \u67e5\u627e\u5217\u8868\u4e2d\u5143\u7d20\u4f4d\u7f6e\u7684\u65b9\u6cd5\u3002<\/p>\n<\/p>\n
                        \u76f8\u5173\u95ee\u7b54FAQs\uff1a<\/strong><\/h2>\n
                         \u5982\u4f55\u5728Python\u4e2d\u67e5\u627e\u5217\u8868\u4e2d\u5143\u7d20\u7684\u7d22\u5f15\uff1f<\/strong>
                        \u5728Python\u4e2d\uff0c\u53ef\u4ee5\u4f7f\u7528list.index()<\/code>\u65b9\u6cd5\u67e5\u627e\u5143\u7d20\u7684\u7d22\u5f15\u3002\u5982\u679c\u5143\u7d20\u5b58\u5728\u4e8e\u5217\u8868\u4e2d\uff0cindex()<\/code>\u65b9\u6cd5\u5c06\u8fd4\u56de\u8be5\u5143\u7d20\u7684\u7b2c\u4e00\u4e2a\u5339\u914d\u9879\u7684\u7d22\u5f15\u3002\u5982\u679c\u5143\u7d20\u4e0d\u5728\u5217\u8868\u4e2d\uff0c\u4f1a\u5f15\u53d1ValueError<\/code>\u3002\u4f8b\u5982\uff1a<\/p>\n
                        my_list = [10, 20, 30, 40]\nindex = my_list.index(30)  # index\u5c06\u4e3a2\n<\/code><\/pre>\n
                        \u4e3a\u4e86\u907f\u514d\u9519\u8bef\uff0c\u53ef\u4ee5\u5148\u4f7f\u7528in<\/code>\u5173\u952e\u5b57\u68c0\u67e5\u5143\u7d20\u662f\u5426\u5b58\u5728\u3002<\/p>\n
                        \u6709\u6ca1\u6709\u5176\u4ed6\u65b9\u6cd5\u53ef\u4ee5\u67e5\u627e\u5217\u8868\u4e2d\u5143\u7d20\u7684\u4f4d\u7f6e\uff1f<\/strong>
                        \u9664\u4e86index()<\/code>\u65b9\u6cd5\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528\u5217\u8868\u63a8\u5bfc\u5f0f\u7ed3\u5408enumerate()<\/code>\u51fd\u6570\uff0c\u83b7\u53d6\u6240\u6709\u5339\u914d\u5143\u7d20\u7684\u7d22\u5f15\u3002\u4f8b\u5982\uff1a<\/p>\n
                        my_list = [10, 20, 30, 20]\nindexes = [i for i, x in enumerate(my_list) if x == 20]  # indexes\u5c06\u4e3a[1, 3]\n<\/code><\/pre>\n
                        \u8fd9\u79cd\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u627e\u5230\u6240\u6709\u5339\u914d\u9879\u7684\u573a\u666f\u3002<\/p>\n
                        \u5982\u4f55\u5904\u7406\u67e5\u627e\u4e0d\u5b58\u5728\u7684\u5143\u7d20\u65f6\u7684\u60c5\u51b5\uff1f<\/strong>
                        \u5728\u67e5\u627e\u5143\u7d20\u65f6\uff0c\u5982\u679c\u4e0d\u786e\u5b9a\u5143\u7d20\u662f\u5426\u5b58\u5728\uff0c\u53ef\u4ee5\u4f7f\u7528try-except<\/code>\u5757\u6765\u5904\u7406\u53ef\u80fd\u7684\u5f02\u5e38\u3002\u4f8b\u5982\uff1a<\/p>\n
                        my_list = [10, 20, 30]\ntry:\n    index = my_list.index(40)\nexcept ValueError:\n    index = -1  # \u6307\u5b9a\u4e00\u4e2a\u9ed8\u8ba4\u503c\u6216\u5176\u4ed6\u5904\u7406\u903b\u8f91\n<\/code><\/pre>\n
                        \u8fd9\u6837\u7684\u5904\u7406\u65b9\u5f0f\u53ef\u4ee5\u786e\u4fdd\u7a0b\u5e8f\u5728\u67e5\u627e\u5931\u8d25\u65f6\u4e0d\u4f1a\u5d29\u6e83\uff0c\u5e76\u5141\u8bb8\u4f60\u8fdb\u884c\u9002\u5f53\u7684\u9519\u8bef\u5904\u7406\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"\u5728 Python \u4e2d\u627e\u5230\u5217\u8868\uff08list\uff09\u4e2d\u5143\u7d20\u7684\u4f4d\u7f6e\u6709\u591a\u79cd\u65b9\u6cd5\uff0c\u5305\u62ec\u4f7f\u7528\u5185\u7f6e\u51fd\u6570\u3001\u5217\u8868\u63a8\u5bfc\u5f0f\u548c\u5916\u90e8\u5e93\u3002\u6700\u5e38\u7528\u7684 […]","protected":false},"author":3,"featured_media":1080092,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[37],"tags":[],"acf":[],"_links":{"self":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1080084"}],"collection":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/comments?post=1080084"}],"version-history":[{"count":"1","href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1080084\/revisions"}],"predecessor-version":[{"id":1080098,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1080084\/revisions\/1080098"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media\/1080092"}],"wp:attachment":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media?parent=1080084"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/categories?post=1080084"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/tags?post=1080084"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}