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writing data to csv from dictionaries with multiple values per key

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问题 Background I am storing data in dictionaries. The dictionaries can be off different length and in a particular dictionary there could be keys with multiple values. I am trying to spit out the data on a CSV file. Problem/Solution Image 1 is how my actual output prints out. Image 2 shows how i would want my output to actually printout. Image 2 is the desired output . CODE import csv from itertools import izip_longest e = {'Lebron':[25,10],'Ray':[40,15]} c = {'Nba':5000} def writeData(): with

Python中7个不一样的代码写法

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打印index 对于一个列表，或者说一个序列我们经常需要打印它的index,一般传统的做法或者说比较low的写法：更优雅的写法是多用enumerate 两个序列的循环我们会经常对两个序列进行计算或者处理，比较low的方法是用下标去循环处理更优雅一点的方法:用zip轻松搞定有没有更优雅的方法呢，比如如果两个序列有10000的长度，当然有的用izip 当然izip还是Py2.x时代的产物，现在Py3.6里面默认zip都是izip了！交换变量多个变量之间的交换，相信很多有c,c++语言基础的同学对这个再熟悉不过了，比如我们经典的冒泡排序，就会用这一招，看看比较传统的做法: 更优雅的做法是：字典的读取字典是我们经常使用的数据结构，对于字典的访问和读取，如果我们的读取的字典的key为空怎么办，一般我们需要一个缺省值,菜鸟的写法: 比较优雅的做法是: 巧妙的利用了字典get的用法，如果字典里面没有Susan这个key,则用unknow来表示缺省值！循环查找我们经常会在一个大的循环中作搜索业务，比如从一个文件中搜索关键字，比如从文件名列表中查找一些特殊的文件名，想当然的写法如下：更优雅的写法：上面的写法是传统的c,c++写法，Python里面有更简洁的写法: 文件读取查找通常来说，我们要打开一个文件，然后对文件的内容进行循环读取和处理，菜鸟的写法如下：更优雅的写法：

importing izip from itertools module gives NameError in Python 3.x

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I am trying to import the izip module like so: from itertools import izip However after recently changing over from Python 2.7 to 3 - it doesn't seem to work. I am trying to write to a csv file: writer.writerows(izip(variable1,2)) But I have no luck. Still encounter an error. In Python 3 the built-in zip does the same job as itertools.izip in 2.X(returns an iterator instead of a list). The zip implementation is almost completely copy-pasted from the old izip , just with a few names changed and pickle support added. Here is a benchmark between zip in Python 2 and 3 and izip in Python 2: Python

importing izip from itertools module gives NameError in Python 3.x

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问题 I am trying to import the izip module like so: from itertools import izip However after recently changing over from Python 2.7 to 3 - it doesn\'t seem to work. I am trying to write to a csv file: writer.writerows(izip(variable1,2)) But I have no luck. Still encounter an error. 回答1: In Python 3 the built-in zip does the same job as itertools.izip in 2.X(returns an iterator instead of a list). The zip implementation is almost completely copy-pasted from the old izip, just with a few names