美元

可以将文章内容翻译成中文,广告屏蔽插件可能会导致该功能失效(如失效，请关闭广告屏蔽插件后再试): 问题: The purpose of this question is to further explore MultiIndex dataframes and to ask questions of the best approach for various tasks. Create the DataFrame import pandas as pd df = pd.DataFrame({'index_date' : ['12/07/2016','12/07/2016','12/07/2016','12/07/2016','12/07/2016'], 'portfolio' : ['A','B','C','D','E'], 'reporting_ccy' : ['GBP','GBP','GBP','GBP','GBP'], 'portfolio_ccy' : ['JPY','USD','USD','EUR','EUR'], 'amount' : [100,200,300,400,500], 'injection' : [1,2,3,4,5], 'to_usd' : [1.3167,1.3167,1.3167,1.3167,1.3167], 'to_ccy' : [0.009564

The cryptocurrency has always been a typical representative of the bubble economy. Since last month, the price of Bitcoin has continued to fall, and the current situation has fallen below 6,000 US dollars. Although it has risen slightly, it has just risen by 6,000. It is not expected that it will rise. Soon to recover, coupled with South Korea's cryptocurrency exchange, Coinrail, said that its system has been "invasion of the network" and may even continue to decline. So what are the reasons that caused the price of bitcoin to continue to fall recently? I think there are the following reasons:

注：本题目来自python123，地址链接：https://python123.io/student/courses/1081/groups/9686/problems/programmings/404 描述 人民币和美元是世界上通用的两种货币之一，写一个程序进行货币间币值转换，其中： 人民币和美元间汇率固定为：1美元 = 6.78人民币。 程序可以接受人民币或美元输入，转换为美元或人民币输出。人民币采用￥符号或RMB表示，美元采用$或USD表示，符号和数值之间没有空格。 注意： (1) 人民币和美元间符号在转换中要对等，￥和$相互对应，RMB和USD相互对应。 输入 示例1：$128.00 示例2：￥12.9 示例3：RMB123 示例4：USD20 输出 对应上述示例的输出是： 示例1：￥867.84 示例2：$1.90 示例3：USD18.14 示例4：RMB135.60 代码如下： a=input("") if a[0]=="$": RMB=eval(a[1:-1]+a[-1])*6.78 print("￥{:.2f}".format(RMB)) elif a[0:3] in ["USD","usd"]: RMB=eval(a[3:-1]+a[-1])*6.78 print("RMB{:.2f}".format(RMB)) elif a[0] == "￥": USD