{"id":1004472,"date":"2024-12-27T10:26:41","date_gmt":"2024-12-27T02:26:41","guid":{"rendered":"https:\/\/docs.pingcode.com\/ask\/ask-ask\/1004472.html"},"modified":"2024-12-27T10:26:44","modified_gmt":"2024-12-27T02:26:44","slug":"python%e4%b8%ad%e5%a6%82%e4%bd%95%e8%bf%94%e5%9b%9e%e7%b4%a2%e5%bc%95","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/1004472.html","title":{"rendered":"python\u4e2d\u5982\u4f55\u8fd4\u56de\u7d22\u5f15"},"content":{"rendered":"

\"python\u4e2d\u5982\u4f55\u8fd4\u56de\u7d22\u5f15\"<\/p>\n

\u5728Python\u4e2d\uff0c\u8fd4\u56de\u7d22\u5f15\u7684\u65b9\u5f0f\u6709\u591a\u79cd\uff0c\u4e3b\u8981\u53d6\u51b3\u4e8e\u4f60\u6240\u4f7f\u7528\u7684\u6570\u636e\u7c7b\u578b\u548c\u5177\u4f53\u9700\u6c42\u3002\u5e38\u89c1\u7684\u65b9\u6cd5\u5305\u62ec\uff1a\u4f7f\u7528\u5217\u8868\u7684index()<\/code>\u65b9\u6cd5\u3001\u901a\u8fc7\u5217\u8868\u63a8\u5bfc\u6216\u751f\u6210\u5668\u8868\u8fbe\u5f0f\u5b9e\u73b0\u81ea\u5b9a\u4e49\u67e5\u627e\u3001\u4ee5\u53ca\u5728NumPy\u6570\u7ec4\u4e2d\u4f7f\u7528where()<\/code>\u51fd\u6570\u3002<\/strong>\u5176\u4e2d\uff0c\u5217\u8868\u7684index()<\/code>\u65b9\u6cd5\u662f\u6700\u76f4\u63a5\u7684\uff0c\u53ef\u4ee5\u7528\u6765\u5feb\u901f\u627e\u5230\u5143\u7d20\u7684\u7d22\u5f15\u3002\u63a5\u4e0b\u6765\uff0c\u6211\u4eec\u5c06\u8be6\u7ec6\u8ba8\u8bba\u8fd9\u4e9b\u65b9\u6cd5\u3002<\/p>\n<\/p>\n

\u4e00\u3001\u4f7f\u7528\u5217\u8868\u7684index()<\/code>\u65b9\u6cd5<\/p>\n<\/p>\n

Python\u7684\u5217\u8868\u63d0\u4f9b\u4e86\u5185\u7f6e\u7684index()<\/code>\u65b9\u6cd5\uff0c\u53ef\u4ee5\u7528\u6765\u67e5\u627e\u6307\u5b9a\u5143\u7d20\u7684\u7b2c\u4e00\u4e2a\u5339\u914d\u9879\u7684\u7d22\u5f15\u3002\u8fd9\u662f\u6700\u5e38\u7528\u7684\u67e5\u627e\u65b9\u6cd5\u4e4b\u4e00\uff0c\u9002\u7528\u4e8e\u67e5\u627e\u5355\u4e2a\u5143\u7d20\u7684\u7d22\u5f15\u3002<\/p>\n<\/p>\n

# \u793a\u4f8b\u4ee3\u7801<\/p>\n
fruits = ['apple', 'banana', 'cherry', 'date']<\/p>\n
index = fruits.index('cherry')<\/p>\n
print(index)  # \u8f93\u51fa\uff1a2<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u5728\u4e0a\u8ff0\u4ee3\u7801\u4e2d\uff0c\u6211\u4eec\u901a\u8fc7\u8c03\u7528index()<\/code>\u65b9\u6cd5\u627e\u5230\u4e86\u5b57\u7b26\u4e32'cherry'\u5728\u5217\u8868\u4e2d\u7684\u7d22\u5f15\u4f4d\u7f6e\u3002\u8fd9\u79cd\u65b9\u6cd5\u7b80\u5355\u76f4\u63a5\uff0c\u4f46\u6709\u4e00\u4e9b\u9650\u5236\uff1a\u5982\u679c\u5143\u7d20\u4e0d\u5b58\u5728\uff0cindex()<\/code>\u65b9\u6cd5\u4f1a\u629b\u51faValueError<\/code>\u5f02\u5e38\u3002\u56e0\u6b64\uff0c\u5728\u4f7f\u7528\u524d\u6700\u597d\u786e\u8ba4\u5143\u7d20\u786e\u5b9e\u5b58\u5728\u4e8e\u5217\u8868\u4e2d\uff0c\u6216\u8005\u7ed3\u5408\u5f02\u5e38\u5904\u7406\u6765\u4f7f\u7528\u3002<\/p>\n<\/p>\n
\u4e8c\u3001\u901a\u8fc7\u5217\u8868\u63a8\u5bfc\u5b9e\u73b0\u81ea\u5b9a\u4e49\u67e5\u627e<\/p>\n<\/p>\n
\u6709\u65f6\u5019\uff0c\u6211\u4eec\u53ef\u80fd\u9700\u8981\u67e5\u627e\u6ee1\u8db3\u7279\u5b9a\u6761\u4ef6\u7684\u6240\u6709\u5143\u7d20\u7684\u7d22\u5f15\uff0c\u8fd9\u65f6\u53ef\u4ee5\u4f7f\u7528\u5217\u8868\u63a8\u5bfc\uff08list comprehensions\uff09\u6765\u5b9e\u73b0\u3002\u8fd9\u79cd\u65b9\u6cd5\u53ef\u4ee5\u7075\u6d3b\u5730\u8fdb\u884c\u6761\u4ef6\u7b5b\u9009\u3002<\/p>\n<\/p>\n
# \u793a\u4f8b\u4ee3\u7801<\/p>\n
numbers = [10, 20, 30, 20, 40, 50]<\/p>\n
indexes = [i for i, num in enumerate(numbers) if num == 20]<\/p>\n
print(indexes)  # \u8f93\u51fa\uff1a[1, 3]<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u5728\u8fd9\u4e2a\u4f8b\u5b50\u4e2d\uff0c\u6211\u4eec\u4f7f\u7528enumerate()<\/code>\u51fd\u6570\u6765\u83b7\u53d6\u5217\u8868\u4e2d\u6bcf\u4e2a\u5143\u7d20\u7684\u7d22\u5f15\u548c\u503c\uff0c\u5e76\u901a\u8fc7\u5217\u8868\u63a8\u5bfc\u6765\u7b5b\u9009\u51fa\u7b26\u5408\u6761\u4ef6\uff08\u503c\u4e3a20\uff09\u7684\u5143\u7d20\u7684\u7d22\u5f15\u3002\u8fd9\u6837\u7684\u65b9\u6cd5\u4e0d\u4ec5\u9002\u7528\u4e8e\u7b80\u5355\u7684\u503c\u5339\u914d\uff0c\u4e5f\u53ef\u4ee5\u7528\u4e8e\u66f4\u590d\u6742\u7684\u6761\u4ef6\u3002<\/p>\n<\/p>\n
\u4e09\u3001\u4f7f\u7528NumPy\u5e93\u7684where()<\/code>\u51fd\u6570<\/p>\n<\/p>\n
\u5bf9\u4e8e\u5927\u578b\u6570\u636e\u96c6\u6216\u9700\u8981\u9ad8\u6027\u80fd\u7684\u7d22\u5f15\u67e5\u627e\u4efb\u52a1\uff0cNumPy\u5e93\u63d0\u4f9b\u4e86\u5f3a\u5927\u7684\u5de5\u5177\u3002where()<\/code>\u51fd\u6570\u53ef\u4ee5\u5e2e\u52a9\u6211\u4eec\u9ad8\u6548\u5730\u67e5\u627e\u6570\u7ec4\u4e2d\u7b26\u5408\u6761\u4ef6\u7684\u5143\u7d20\u7684\u7d22\u5f15\u3002<\/p>\n<\/p>\n
# \u793a\u4f8b\u4ee3\u7801<\/p>\n
import numpy as np<\/p>\n
array = np.array([10, 20, 30, 20, 40, 50])<\/p>\n
indexes = np.where(array == 20)<\/p>\n
print(indexes)  # \u8f93\u51fa\uff1a(array([1, 3]),)<\/p>\n
<\/code><\/pre>\n<\/p>\n
NumPy\u7684where()<\/code>\u51fd\u6570\u8fd4\u56de\u4e00\u4e2a\u5143\u7ec4\uff0c\u5176\u4e2d\u5305\u542b\u4e86\u6ee1\u8db3\u6761\u4ef6\u7684\u5143\u7d20\u7684\u7d22\u5f15\u3002\u8fd9\u79cd\u65b9\u6cd5\u5728\u5904\u7406\u5927\u578b\u6570\u7ec4\u65f6\u5177\u6709\u663e\u8457\u7684\u6027\u80fd\u4f18\u52bf\uff0c\u56e0\u4e3aNumPy\u7684\u5e95\u5c42\u5b9e\u73b0\u662f\u57fa\u4e8eC\u8bed\u8a00\u7684\uff0c\u80fd\u591f\u8fdb\u884c\u5feb\u901f\u7684\u6570\u503c\u8ba1\u7b97\u3002<\/p>\n<\/p>\n
\u56db\u3001\u4f7f\u7528\u5b57\u5178\u7684\u952e\u67e5\u627e<\/p>\n<\/p>\n
\u5982\u679c\u6570\u636e\u5b58\u50a8\u5728\u5b57\u5178\u4e2d\uff0c\u67e5\u627e\u7d22\u5f15\u7684\u601d\u8def\u4f1a\u6709\u6240\u4e0d\u540c\uff0c\u56e0\u4e3a\u5b57\u5178\u662f\u952e\u503c\u5bf9\u7684\u96c6\u5408\u3002\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0c\u901a\u5e38\u901a\u8fc7\u952e\u6765\u8bbf\u95ee\u5bf9\u5e94\u7684\u503c\uff0c\u800c\u4e0d\u662f\u901a\u8fc7\u7d22\u5f15\u8bbf\u95ee\u3002<\/p>\n<\/p>\n
# \u793a\u4f8b\u4ee3\u7801<\/p>\n
student_scores = {'Alice': 85, 'Bob': 92, 'Charlie': 78}<\/p>\n
score = student_scores['Bob']<\/p>\n
print(score)  # \u8f93\u51fa\uff1a92<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u5b57\u5178\u7684\u67e5\u627e\u64cd\u4f5c\u662f\u57fa\u4e8e\u952e\u8fdb\u884c\u7684\uff0c\u56e0\u6b64\u5728\u8fd9\u79cd\u6570\u636e\u7ed3\u6784\u4e2d\u4e0d\u9002\u7528\u7d22\u5f15\u7684\u6982\u5ff5\u3002\u4e0d\u8fc7\uff0c\u5982\u679c\u9700\u8981\u6839\u636e\u503c\u6765\u627e\u5230\u5bf9\u5e94\u7684\u952e\uff0c\u53ef\u4ee5\u8fdb\u884c\u53cd\u5411\u67e5\u627e\uff1a<\/p>\n<\/p>\n
# \u793a\u4f8b\u4ee3\u7801<\/p>\n
name_for_score = {v: k for k, v in student_scores.items()}<\/p>\n
name = name_for_score[92]<\/p>\n
print(name)  # \u8f93\u51fa\uff1aBob<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u901a\u8fc7\u5b57\u5178\u63a8\u5bfc\uff0c\u6211\u4eec\u521b\u5efa\u4e86\u4e00\u4e2a\u53cd\u5411\u67e5\u627e\u7684\u5b57\u5178\uff0c\u53ef\u4ee5\u901a\u8fc7\u503c\u6765\u83b7\u53d6\u5bf9\u5e94\u7684\u952e\u3002\u8fd9\u79cd\u65b9\u6cd5\u9002\u7528\u4e8e\u9700\u8981\u5feb\u901f\u53cd\u5411\u67e5\u627e\u7684\u60c5\u51b5\u3002<\/p>\n<\/p>\n
\u4e94\u3001\u603b\u7ed3<\/p>\n<\/p>\n
\u5728Python\u4e2d\uff0c\u8fd4\u56de\u7d22\u5f15\u7684\u65b9\u6cd5\u591a\u79cd\u591a\u6837\uff0c\u5177\u4f53\u9009\u62e9\u53d6\u51b3\u4e8e\u6570\u636e\u7ed3\u6784\u548c\u9700\u6c42\u3002\u5bf9\u4e8e\u5217\u8868\uff0cindex()<\/code>\u65b9\u6cd5\u662f\u6700\u76f4\u63a5\u7684\u9009\u62e9\uff1b\u5bf9\u4e8e\u590d\u6742\u6761\u4ef6\u7684\u67e5\u627e\uff0c\u5217\u8868\u63a8\u5bfc\u63d0\u4f9b\u4e86\u7075\u6d3b\u6027\uff1bNumPy\u7684where()<\/code>\u51fd\u6570\u5728\u5904\u7406\u5927\u89c4\u6a21\u6570\u7ec4\u65f6\u63d0\u4f9b\u4e86\u6027\u80fd\u4f18\u52bf\uff1b\u5bf9\u4e8e\u5b57\u5178\uff0c\u901a\u5e38\u901a\u8fc7\u952e\u8fdb\u884c\u67e5\u627e\uff0c\u4f46\u4e5f\u53ef\u4ee5\u4f7f\u7528\u53cd\u5411\u5b57\u5178\u8fdb\u884c\u503c\u67e5\u627e\u3002<\/strong>\u4e86\u89e3\u8fd9\u4e9b\u65b9\u6cd5\u7684\u9002\u7528\u573a\u666f\u548c\u9650\u5236\uff0c\u53ef\u4ee5\u5e2e\u52a9\u4f60\u5728\u5b9e\u9645\u7f16\u7a0b\u4e2d\u9009\u62e9\u6700\u5408\u9002\u7684\u89e3\u51b3\u65b9\u6848\u3002<\/p>\n<\/p>\n
\u76f8\u5173\u95ee\u7b54FAQs\uff1a<\/strong><\/h2>\n
 \u5728Python\u4e2d\uff0c\u5982\u4f55\u67e5\u627e\u5143\u7d20\u7684\u7d22\u5f15\uff1f<\/strong>
\u5728Python\u4e2d\uff0c\u53ef\u4ee5\u4f7f\u7528\u5217\u8868\u7684index()<\/code>\u65b9\u6cd5\u6765\u67e5\u627e\u5143\u7d20\u7684\u7d22\u5f15\u3002\u4f8b\u5982\uff0c\u5047\u8bbe\u6709\u4e00\u4e2a\u5217\u8868my_list = [10, 20, 30, 40]<\/code>\uff0c\u5982\u679c\u60f3\u8981\u627e\u51fa\u5143\u7d2030<\/code>\u7684\u7d22\u5f15\uff0c\u53ef\u4ee5\u4f7f\u7528my_list.index(30)<\/code>\uff0c\u7ed3\u679c\u5c06\u8fd4\u56de2<\/code>\uff0c\u56e0\u4e3a30<\/code>\u5728\u5217\u8868\u4e2d\u7684\u4f4d\u7f6e\u662f\u7b2c\u4e09\u4e2a\uff08\u7d22\u5f15\u4ece0\u5f00\u59cb\uff09\u3002<\/p>\n
\u5982\u679c\u5143\u7d20\u5728\u5217\u8868\u4e2d\u4e0d\u5b58\u5728\uff0c\u5982\u4f55\u5904\u7406\u9519\u8bef\uff1f<\/strong>
\u5f53\u4f7f\u7528index()<\/code>\u65b9\u6cd5\u67e5\u627e\u4e0d\u5b58\u5728\u7684\u5143\u7d20\u65f6\uff0c\u4f1a\u5f15\u53d1ValueError<\/code>\u3002\u4e3a\u4e86\u907f\u514d\u7a0b\u5e8f\u5d29\u6e83\uff0c\u53ef\u4ee5\u4f7f\u7528try...except<\/code>\u8bed\u53e5\u3002\u4f8b\u5982\uff1a  <\/p>\n
try:\n    index = my_list.index(50)\nexcept ValueError:\n    index = -1  # \u8fd4\u56de-1\u8868\u793a\u672a\u627e\u5230\n<\/code><\/pre>\n
\u8fd9\u6837\uff0c\u5373\u4f7f\u5143\u7d20\u4e0d\u5b58\u5728\uff0c\u7a0b\u5e8f\u4ecd\u7136\u53ef\u4ee5\u6b63\u5e38\u8fd0\u884c\uff0c\u5e76\u8fd4\u56de\u4e00\u4e2a\u7279\u5b9a\u7684\u503c\u3002<\/p>\n
\u5728Python\u4e2d\uff0c\u5982\u4f55\u83b7\u53d6\u591a\u4e2a\u76f8\u540c\u5143\u7d20\u7684\u7d22\u5f15\uff1f<\/strong>
\u5982\u679c\u9700\u8981\u67e5\u627e\u5217\u8868\u4e2d\u6240\u6709\u76f8\u540c\u5143\u7d20\u7684\u7d22\u5f15\uff0c\u53ef\u4ee5\u4f7f\u7528\u5217\u8868\u63a8\u5bfc\u5f0f\u7ed3\u5408enumerate()<\/code>\u51fd\u6570\u3002\u4ee5\u4e0b\u662f\u4e00\u4e2a\u793a\u4f8b\uff1a  <\/p>\n
my_list = [10, 20, 30, 20, 40]\nindexes = [i for i, x in enumerate(my_list) if x == 20]\n<\/code><\/pre>\n
\u5728\u8fd9\u4e2a\u4f8b\u5b50\u4e2d\uff0cindexes<\/code>\u5c06\u5305\u542b[1, 3]<\/code>\uff0c\u8868\u793a20<\/code>\u5728\u5217\u8868\u4e2d\u7684\u4f4d\u7f6e\u3002\u8fd9\u6837\u7684\u65b9\u6cd5\u975e\u5e38\u6709\u6548\uff0c\u7279\u522b\u662f\u5728\u5904\u7406\u5305\u542b\u91cd\u590d\u5143\u7d20\u7684\u5217\u8868\u65f6\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"\u5728Python\u4e2d\uff0c\u8fd4\u56de\u7d22\u5f15\u7684\u65b9\u5f0f\u6709\u591a\u79cd\uff0c\u4e3b\u8981\u53d6\u51b3\u4e8e\u4f60\u6240\u4f7f\u7528\u7684\u6570\u636e\u7c7b\u578b\u548c\u5177\u4f53\u9700\u6c42\u3002\u5e38\u89c1\u7684\u65b9\u6cd5\u5305\u62ec\uff1a\u4f7f\u7528\u5217\u8868\u7684in […]","protected":false},"author":3,"featured_media":1004481,"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\/1004472"}],"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=1004472"}],"version-history":[{"count":"1","href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1004472\/revisions"}],"predecessor-version":[{"id":1004485,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1004472\/revisions\/1004485"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media\/1004481"}],"wp:attachment":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media?parent=1004472"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/categories?post=1004472"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/tags?post=1004472"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}