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以前的写法: key_list = my_dict.keys() first_key = my_dict.keys()[0] 但是现在会报错,原因在于keys()方法现在会返回一个字典,而非列表。 现在的写法: key_list = list(my_dict.keys()) first_key = 阅读全文
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读JSON或txt文件常用: with open(new_path, 'r', encoding='utf-8') as file: data = json.load(file) ''' to do ''' json.loads()和json.load()都是将操作对象转换成Python对象,其中j 阅读全文
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dict_list = [] for ...: dict = {"key": "value"} dict_list.append(dict) # 使用 json.dumps 将列表转换为 JSON 字符串 result = ',\n'.join(json.dumps(d, ensure_ascii= 阅读全文
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遍历dict对象用items()方法 for id, content in json.load(open('test.json', 'r', encoding='utf-8')).items(): items()返回<key, value>键值对。 其中json.load()将json对象转化为py 阅读全文
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学习一下pandas中对excel操作的三种情况(xlwt, xlsxwriter和openpyxl):python写Excel的三个选项:xlwt, xlsxwriter和openpyxl_xlwt不能创建.xlsx格式的文件吗-CSDN博客 想要写一个xls文件,按照上文博客的说法,只有xlwt 阅读全文
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Problem 17.9. A foreign currency is currently worth $1.50. The domestic and foreign risk-free interest rates are 5% and 9%, respectively. Calculate a 阅读全文
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Problem 13.1. A stock price is currently $40. It is known that at the end of one month it will be either $42 or $38. The risk-free interest rate is 8% 阅读全文
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Problem 10.11. Describe the terminal value of the following portfolio: a newly entered-into long forward contract on an asset and a long position in a 阅读全文
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第2章 Problem 2.3. Suppose that you enter into a short futures contract to sell July silver for $17.20 per ounce. The size of the contract is 5,000 ounc 阅读全文
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一、分析说明题 在数据库系统应用为公众提供信息服务过程中,为什么要求对运营者和维护管理人员实施严格的法规与职业道德约束?从技术层面如何保护用户个人隐私和机构商业机密? 答: IT行业的快速发展给人类的交往、学习、工作和生活带来很多便利,极大地推动了社会的进步。但同时,计算机病毒、黑客、信息泄露等问题 阅读全文