{"id":1004242,"date":"2024-12-27T10:24:38","date_gmt":"2024-12-27T02:24:38","guid":{"rendered":"https:\/\/docs.pingcode.com\/ask\/ask-ask\/1004242.html"},"modified":"2024-12-27T10:24:42","modified_gmt":"2024-12-27T02:24:42","slug":"python%e5%a6%82%e4%bd%95%e5%ae%9a%e4%b9%89%e5%b0%8f%e6%95%b0%e7%b1%bb%e5%9e%8b","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/1004242.html","title":{"rendered":"python\u5982\u4f55\u5b9a\u4e49\u5c0f\u6570\u7c7b\u578b"},"content":{"rendered":"

\"python\u5982\u4f55\u5b9a\u4e49\u5c0f\u6570\u7c7b\u578b\"<\/p>\n

Python\u4e2d\u5b9a\u4e49\u5c0f\u6570\u7c7b\u578b\u53ef\u4ee5\u4f7f\u7528float<\/code>\u3001decimal.Decimal<\/code>\u3001fractions.Fraction<\/code>\u7b49\u65b9\u5f0f\uff0c\u901a\u5e38\u4f7f\u7528float<\/code>\u3001decimal.Decimal<\/code>\u5904\u7406\u9ad8\u7cbe\u5ea6\u8ba1\u7b97\u3002<\/strong> float<\/code>\u662fPython\u5185\u7f6e\u7684\u6570\u636e\u7c7b\u578b\uff0c\u9002\u7528\u4e8e\u5927\u591a\u6570\u65e5\u5e38\u8ba1\u7b97\uff0c\u4f46\u7531\u4e8e\u5176\u5e95\u5c42\u5b9e\u73b0\u91c7\u7528\u4e8c\u8fdb\u5236\u6d6e\u70b9\u6570\uff0c\u53ef\u80fd\u4f1a\u5f15\u5165\u7cbe\u5ea6\u8bef\u5dee\u3002\u5982\u679c\u9700\u8981\u66f4\u9ad8\u7cbe\u5ea6\u7684\u8ba1\u7b97\uff0c\u63a8\u8350\u4f7f\u7528decimal.Decimal<\/code>\u3002fractions.Fraction<\/code>\u63d0\u4f9b\u4e86\u5206\u6570\u8868\u793a\u6cd5\uff0c\u53ef\u4ee5\u7528\u4e8e\u4e00\u4e9b\u7279\u5b9a\u573a\u5408\u3002\u4e0b\u9762\u5c06\u8be6\u7ec6\u4ecb\u7ecd\u8fd9\u51e0\u79cd\u65b9\u5f0f\u3002<\/p>\n<\/p>\n

\u4e00\u3001FLOAT\u7c7b\u578b<\/p>\n<\/p>\n

float<\/code>\u662fPython\u4e2d\u6700\u5e38\u7528\u7684\u5c0f\u6570\u7c7b\u578b\uff0c\u5b83\u662f\u4e00\u4e2a\u53cc\u7cbe\u5ea6\u6d6e\u70b9\u6570\uff0c\u80fd\u591f\u6ee1\u8db3\u5927\u90e8\u5206\u65e5\u5e38\u8ba1\u7b97\u9700\u6c42\u3002<\/p>\n<\/p>\n

    \n
  1. \n

    \u57fa\u672c\u7528\u6cd5<\/strong><\/p>\n<\/p>\n

    \u5728Python\u4e2d\uff0cfloat<\/code>\u7c7b\u578b\u7684\u6570\u503c\u901a\u5e38\u901a\u8fc7\u76f4\u63a5\u8d4b\u503c\u6216\u8fd0\u7b97\u8868\u8fbe\u5f0f\u5f97\u5230\u3002\u4f8b\u5982\uff1a<\/p>\n<\/p>\n

    x = 3.14<\/p>\n
    y = 1.0 \/ 3.0<\/p>\n
    <\/code><\/pre>\n<\/p>\n
    \u4e0a\u8ff0\u4ee3\u7801\u4e2d\uff0cx<\/code>\u548cy<\/code>\u90fd\u662ffloat<\/code>\u7c7b\u578b\u3002<\/p>\n<\/p>\n<\/li>\n
  2. \n
    \u6ce8\u610f\u4e8b\u9879<\/strong><\/p>\n<\/p>\n
    \u867d\u7136float<\/code>\u5728\u591a\u6570\u60c5\u51b5\u4e0b\u90fd\u80fd\u6ee1\u8db3\u9700\u6c42\uff0c\u4f46\u7531\u4e8e\u5176\u5e95\u5c42\u57fa\u4e8e\u4e8c\u8fdb\u5236\u6d6e\u70b9\u6570\uff0c\u67d0\u4e9b\u60c5\u51b5\u4e0b\u4f1a\u5f15\u5165\u7cbe\u5ea6\u8bef\u5dee\u3002\u4f8b\u5982\uff1a<\/p>\n<\/p>\n
    print(0.1 + 0.2)  # \u8f93\u51fa0.30000000000000004<\/p>\n
    <\/code><\/pre>\n<\/p>\n
    \u8fd9\u79cd\u8bef\u5dee\u6e90\u4e8e\u4e8c\u8fdb\u5236\u6d6e\u70b9\u6570\u65e0\u6cd5\u7cbe\u786e\u8868\u793a\u67d0\u4e9b\u5341\u8fdb\u5236\u6570\u3002<\/p>\n<\/p>\n<\/li>\n<\/ol>\n
    \u4e8c\u3001DECIMAL\u7c7b\u578b<\/p>\n<\/p>\n
    decimal.Decimal<\/code>\u63d0\u4f9b\u4e86\u66f4\u9ad8\u7cbe\u5ea6\u7684\u6d6e\u70b9\u6570\u8868\u793a\uff0c\u9002\u7528\u4e8e\u9700\u8981\u4e25\u683c\u63a7\u5236\u7cbe\u5ea6\u7684\u573a\u5408\u3002<\/p>\n<\/p>\n
      \n
    1. \n
      \u57fa\u672c\u7528\u6cd5<\/strong><\/p>\n<\/p>\n
      \u4f7f\u7528decimal<\/code>\u6a21\u5757\u53ef\u4ee5\u5b9a\u4e49\u9ad8\u7cbe\u5ea6\u7684\u5c0f\u6570\u3002\u9996\u5148\u9700\u8981\u5bfc\u5165\u6a21\u5757\uff1a<\/p>\n<\/p>\n
      from decimal import Decimal<\/p>\n
      a = Decimal('0.1')<\/p>\n
      b = Decimal('0.2')<\/p>\n
      result = a + b<\/p>\n
      print(result)  # \u8f93\u51fa0.3<\/p>\n
      <\/code><\/pre>\n<\/p>\n
      \u8fd9\u91cc\u901a\u8fc7\u5b57\u7b26\u4e32\u4f20\u9012\u6570\u503c\u4ee5\u907f\u514dfloat<\/code>\u7684\u7cbe\u5ea6\u95ee\u9898\u3002<\/p>\n<\/p>\n<\/li>\n
    2. \n
      \u8bbe\u7f6e\u7cbe\u5ea6<\/strong><\/p>\n<\/p>\n
      decimal<\/code>\u6a21\u5757\u8fd8\u5141\u8bb8\u8bbe\u7f6e\u5168\u5c40\u6216\u5c40\u90e8\u8ba1\u7b97\u7cbe\u5ea6\u3002\u4f8b\u5982\uff1a<\/p>\n<\/p>\n
      from decimal import getcontext, Decimal<\/p>\n
      getcontext().prec = 5  # \u8bbe\u7f6e\u5168\u5c40\u7cbe\u5ea6<\/p>\n
      a = Decimal('1.12345')<\/p>\n
      b = Decimal('1.12345')<\/p>\n
      print(a + b)  # \u8f93\u51fa2.2469<\/p>\n
      <\/code><\/pre>\n<\/p>\n
      \u53ef\u4ee5\u770b\u5230\uff0c\u7ed3\u679c\u88ab\u622a\u65ad\u81f3\u56db\u4f4d\u5c0f\u6570\u3002<\/p>\n<\/p>\n<\/li>\n<\/ol>\n
      \u4e09\u3001FRACTIONS\u7c7b\u578b<\/p>\n<\/p>\n
      fractions.Fraction<\/code>\u63d0\u4f9b\u4e86\u4e00\u79cd\u5206\u6570\u8868\u793a\u6cd5\uff0c\u53ef\u4ee5\u907f\u514d\u6d6e\u70b9\u6570\u7684\u7cbe\u5ea6\u95ee\u9898\u3002<\/p>\n<\/p>\n
        \n
      1. \n
        \u57fa\u672c\u7528\u6cd5<\/strong><\/p>\n<\/p>\n
        fractions<\/code>\u6a21\u5757\u5141\u8bb8\u5b9a\u4e49\u5206\u6570\uff0c\u5e76\u652f\u6301\u7b97\u672f\u8fd0\u7b97\uff1a<\/p>\n<\/p>\n
        from fractions import Fraction<\/p>\n
        f = Fraction(1, 3)<\/p>\n
        print(f)  # \u8f93\u51fa1\/3<\/p>\n
        result = f + Fraction(1, 3)<\/p>\n
        print(result)  # \u8f93\u51fa2\/3<\/p>\n
        <\/code><\/pre>\n<\/p>\n
        \u8fd9\u79cd\u8868\u793a\u6cd5\u907f\u514d\u4e86\u6d6e\u70b9\u6570\u7684\u7cbe\u5ea6\u8bef\u5dee\u3002<\/p>\n<\/p>\n<\/li>\n
      2. \n
        \u5e94\u7528\u573a\u666f<\/strong><\/p>\n<\/p>\n
        fractions.Fraction<\/code>\u9002\u7528\u4e8e\u9700\u8981\u7cbe\u786e\u5206\u6570\u8fd0\u7b97\u7684\u573a\u5408\uff0c\u4f8b\u5982\u6570\u5b66\u8ba1\u7b97\u548c\u4e00\u4e9b\u79d1\u5b66\u5e94\u7528\u3002\u4f46\u7531\u4e8e\u6027\u80fd\u95ee\u9898\uff0c\u4e0d\u5efa\u8bae\u5728\u5927\u91cf\u8ba1\u7b97\u4e2d\u4f7f\u7528\u3002<\/p>\n<\/p>\n<\/li>\n<\/ol>\n
        \u56db\u3001\u4e0d\u540c\u7c7b\u578b\u7684\u5bf9\u6bd4<\/p>\n<\/p>\n
          \n
        1. \n
          \u7cbe\u5ea6\u5bf9\u6bd4<\/strong><\/p>\n<\/p>\n
            \n
          • float<\/code>\uff1a\u9002\u5408\u591a\u6570\u65e5\u5e38\u5e94\u7528\uff0c\u4f46\u53ef\u80fd\u5b58\u5728\u7cbe\u5ea6\u8bef\u5dee\u3002<\/li>\n
          • decimal.Decimal<\/code>\uff1a\u9ad8\u7cbe\u5ea6\uff0c\u9002\u7528\u4e8e\u91d1\u878d\u3001\u79d1\u5b66\u8ba1\u7b97\u7b49\u9700\u8981\u7cbe\u786e\u7ed3\u679c\u7684\u573a\u5408\u3002<\/li>\n
          • fractions.Fraction<\/code>\uff1a\u7cbe\u786e\u5206\u6570\u8868\u793a\uff0c\u9002\u7528\u4e8e\u7279\u5b9a\u6570\u5b66\u8ba1\u7b97\u3002<\/li>\n<\/ul>\n<\/li>\n
          • \n
            \u6027\u80fd\u5bf9\u6bd4<\/strong><\/p>\n<\/p>\n
              \n
            • float<\/code>\uff1a\u6027\u80fd\u6700\u4f73\uff0c\u9002\u5408\u5927\u89c4\u6a21\u8ba1\u7b97\u3002<\/li>\n
            • decimal.Decimal<\/code>\uff1a\u6027\u80fd\u8f83\u5dee\uff0c\u9002\u5408\u5c11\u91cf\u9ad8\u7cbe\u5ea6\u8ba1\u7b97\u3002<\/li>\n
            • fractions.Fraction<\/code>\uff1a\u6027\u80fd\u6700\u5dee\uff0c\u4e0d\u9002\u5408\u5927\u89c4\u6a21\u8fd0\u7b97\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n
              \u4e94\u3001\u5b9e\u8df5\u5e94\u7528<\/p>\n<\/p>\n
                \n
              1. \n
                \u91d1\u878d\u8ba1\u7b97<\/strong><\/p>\n<\/p>\n
                \u5728\u91d1\u878d\u5e94\u7528\u4e2d\uff0cdecimal.Decimal<\/code>\u662f\u9996\u9009\uff0c\u56e0\u4e3a\u91d1\u878d\u8ba1\u7b97\u9700\u8981\u4e25\u683c\u7684\u7cbe\u5ea6\u63a7\u5236\u3002\u4f8b\u5982\uff1a<\/p>\n<\/p>\n
                from decimal import Decimal<\/p>\n
                price = Decimal('19.99')<\/p>\n
                quantity = Decimal('3')<\/p>\n
                total = price * quantity<\/p>\n
                print(total)  # \u8f93\u51fa59.97<\/p>\n
                <\/code><\/pre>\n<\/p>\n
                \u4f7f\u7528Decimal<\/code>\u53ef\u4ee5\u907f\u514d\u56e0\u6d6e\u70b9\u6570\u7cbe\u5ea6\u95ee\u9898\u5bfc\u81f4\u7684\u8d22\u52a1\u8ba1\u7b97\u9519\u8bef\u3002<\/p>\n<\/p>\n<\/li>\n
              2. \n
                \u79d1\u5b66\u8ba1\u7b97<\/strong><\/p>\n<\/p>\n
                \u5728\u79d1\u5b66\u8ba1\u7b97\u4e2d\uff0cfloat<\/code>\u548cdecimal.Decimal<\/code>\u90fd\u53ef\u80fd\u4f7f\u7528\u3002\u5bf9\u4e8e\u9700\u8981\u5927\u91cf\u8ba1\u7b97\u4e14\u5bf9\u7cbe\u5ea6\u8981\u6c42\u4e0d\u9ad8\u7684\u573a\u5408\uff0cfloat<\/code>\u662f\u4e0d\u9519\u7684\u9009\u62e9\uff0c\u800c\u5bf9\u7cbe\u5ea6\u8981\u6c42\u8f83\u9ad8\u7684\u90e8\u5206\uff0cdecimal.Decimal<\/code>\u66f4\u4e3a\u5408\u9002\u3002<\/p>\n<\/p>\n<\/li>\n
              3. \n
                \u6570\u5b66\u8fd0\u7b97<\/strong><\/p>\n<\/p>\n
                \u5bf9\u4e8e\u67d0\u4e9b\u9700\u8981\u5206\u6570\u8868\u793a\u7684\u6570\u5b66\u8fd0\u7b97\uff0cfractions.Fraction<\/code>\u662f\u4e00\u4e2a\u7406\u60f3\u7684\u9009\u62e9\u3002\u4f8b\u5982\u8ba1\u7b97\u7ec4\u5408\u6570\u3001\u6982\u7387\u7b49\u5e94\u7528\u4e2d\uff0c\u53ef\u4ee5\u907f\u514d\u7cbe\u5ea6\u8bef\u5dee\u3002<\/p>\n<\/p>\n<\/li>\n<\/ol>\n
                \u603b\u7ed3\u6765\u8bf4\uff0cPython\u63d0\u4f9b\u4e86\u591a\u79cd\u65b9\u5f0f\u6765\u5b9a\u4e49\u5c0f\u6570\u7c7b\u578b\uff0c\u4ee5\u6ee1\u8db3\u4e0d\u540c\u573a\u5408\u7684\u9700\u6c42\u3002\u5728\u9009\u62e9\u5177\u4f53\u7c7b\u578b\u65f6\uff0c\u5e94\u6839\u636e\u8ba1\u7b97\u7684\u7cbe\u5ea6\u9700\u6c42\u3001\u6027\u80fd\u8981\u6c42\u4ee5\u53ca\u5177\u4f53\u5e94\u7528\u573a\u666f\u6765\u505a\u51fa\u51b3\u5b9a\u3002float<\/code>\u9002\u5408\u4e00\u822c\u7528\u9014\uff0cdecimal.Decimal<\/code>\u9002\u5408\u9ad8\u7cbe\u5ea6\u8ba1\u7b97\uff0c\u800cfractions.Fraction<\/code>\u5219\u9002\u7528\u4e8e\u7279\u5b9a\u6570\u5b66\u8ba1\u7b97\u3002<\/p>\n<\/p>\n
                \u76f8\u5173\u95ee\u7b54FAQs\uff1a<\/strong><\/h2>\n
                 \u5982\u4f55\u5728Python\u4e2d\u521b\u5efa\u5c0f\u6570\u7c7b\u578b\u7684\u53d8\u91cf\uff1f<\/strong>
                \u5728Python\u4e2d\uff0c\u53ef\u4ee5\u901a\u8fc7\u76f4\u63a5\u8d4b\u503c\u7684\u65b9\u5f0f\u521b\u5efa\u5c0f\u6570\u7c7b\u578b\u7684\u53d8\u91cf\u3002\u53ea\u9700\u5c06\u4e00\u4e2a\u5305\u542b\u5c0f\u6570\u70b9\u7684\u6570\u5b57\u8d4b\u7ed9\u4e00\u4e2a\u53d8\u91cf\uff0c\u4f8b\u5982\uff1amy_decimal = 3.14<\/code>\u3002\u6b64\u5916\uff0cPython\u7684\u6d6e\u70b9\u6570\u9ed8\u8ba4\u7cbe\u5ea6\u8db3\u4ee5\u5904\u7406\u5927\u591a\u6570\u5c0f\u6570\u8fd0\u7b97\uff0c\u4f46\u5bf9\u4e8e\u91d1\u878d\u8ba1\u7b97\u7b49\u9700\u8981\u9ad8\u7cbe\u5ea6\u7684\u5c0f\u6570\uff0c\u5efa\u8bae\u4f7f\u7528decimal<\/code>\u6a21\u5757\u3002<\/p>\n
                \u4f7f\u7528Python\u7684Decimal\u6a21\u5757\u6709\u4ec0\u4e48\u597d\u5904\uff1f<\/strong>
                \u4f7f\u7528Python\u7684decimal<\/code>\u6a21\u5757\u53ef\u4ee5\u63d0\u4f9b\u6bd4\u6d6e\u70b9\u6570\u66f4\u9ad8\u7684\u7cbe\u5ea6\u548c\u66f4\u597d\u7684\u820d\u5165\u63a7\u5236\u3002\u8fd9\u4e2a\u6a21\u5757\u7279\u522b\u9002\u7528\u4e8e\u9700\u8981\u7cbe\u786e\u8ba1\u7b97\u7684\u5c0f\u6570\u8fd0\u7b97\uff0c\u6bd4\u5982\u8d22\u52a1\u5e94\u7528\u3002\u901a\u8fc7from decimal import Decimal<\/code>\uff0c\u53ef\u4ee5\u521b\u5efa\u4e00\u4e2aDecimal\u5bf9\u8c61\uff0c\u4f8b\u5982\uff1amy_decimal = Decimal('3.14')<\/code>\u3002\u8fd9\u6837\u53ef\u4ee5\u907f\u514d\u6d6e\u70b9\u6570\u8ba1\u7b97\u4e2d\u5e38\u89c1\u7684\u7cbe\u5ea6\u8bef\u5dee\u3002<\/p>\n
                \u5982\u4f55\u8fdb\u884c\u5c0f\u6570\u7684\u56db\u820d\u4e94\u5165\u64cd\u4f5c\uff1f<\/strong>
                \u5728Python\u4e2d\uff0c\u53ef\u4ee5\u4f7f\u7528round()<\/code>\u51fd\u6570\u5bf9\u5c0f\u6570\u8fdb\u884c\u56db\u820d\u4e94\u5165\u3002\u4f8b\u5982\uff0crounded_value = round(my_decimal, 2)<\/code>\u4f1a\u5c06my_decimal<\/code>\u4fdd\u7559\u4e24\u4f4d\u5c0f\u6570\u3002\u5bf9\u4e8e\u4f7f\u7528decimal<\/code>\u6a21\u5757\u7684Decimal\u5bf9\u8c61\uff0c\u53ef\u4ee5\u4f7f\u7528quantize()<\/code>\u65b9\u6cd5\u6765\u5b9e\u73b0\u66f4\u7cbe\u786e\u7684\u820d\u5165\u3002\u4f8b\u5982\uff1amy_decimal.quantize(Decimal('0.01'))<\/code>\u5c06\u4f1a\u628aDecimal\u5bf9\u8c61\u4fdd\u7559\u4e24\u4f4d\u5c0f\u6570\u3002<\/p>\n
                \u5728Python\u4e2d\u5c0f\u6570\u548c\u6d6e\u70b9\u6570\u7684\u533a\u522b\u662f\u4ec0\u4e48\uff1f<\/strong>
                \u5c0f\u6570\uff08Decimal\uff09\u548c\u6d6e\u70b9\u6570\uff08float\uff09\u5728\u5b58\u50a8\u548c\u8ba1\u7b97\u4e0a\u6709\u6240\u4e0d\u540c\u3002\u6d6e\u70b9\u6570\u4f7f\u7528\u4e8c\u8fdb\u5236\u8868\u793a\uff0c\u53ef\u80fd\u5bfc\u81f4\u7cbe\u5ea6\u4e22\u5931\uff0c\u9002\u5408\u5927\u90e8\u5206\u79d1\u5b66\u8ba1\u7b97\u3002\u800c\u5c0f\u6570\u4f7f\u7528\u5341\u8fdb\u5236\u8868\u793a\uff0c\u80fd\u591f\u7cbe\u786e\u8868\u793a\u5c0f\u6570\uff0c\u907f\u514d\u4e86\u6d6e\u70b9\u6570\u7684\u7cbe\u5ea6\u95ee\u9898\uff0c\u66f4\u9002\u5408\u8d22\u52a1\u8ba1\u7b97\u7b49\u5bf9\u7cbe\u5ea6\u6709\u4e25\u683c\u8981\u6c42\u7684\u573a\u5408\u3002\u9009\u62e9\u4f55\u79cd\u7c7b\u578b\u53d6\u51b3\u4e8e\u5177\u4f53\u7684\u5e94\u7528\u573a\u666f\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"Python\u4e2d\u5b9a\u4e49\u5c0f\u6570\u7c7b\u578b\u53ef\u4ee5\u4f7f\u7528float\u3001decimal.Decimal\u3001fractions.Fracti […]","protected":false},"author":3,"featured_media":1004256,"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\/1004242"}],"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=1004242"}],"version-history":[{"count":"1","href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1004242\/revisions"}],"predecessor-version":[{"id":1004258,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1004242\/revisions\/1004258"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media\/1004256"}],"wp:attachment":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media?parent=1004242"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/categories?post=1004242"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/tags?post=1004242"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}