What does the 'b' character do in front of a string literal?

Apparently, the following is valid syntax my_string = b'The string' I would like to know: What does this b character in front of the string mean? What are the effects of using it? What are appropriate situations to use it? I found a related question right here on SO, but that question is about PHP though, and it states the b is used to indicate the string is binary, as opposed to Unicod

'b'字符在字符串前面做了什么?

显然,以下是有效的语法 my_string = b'The string' 我想知道: 字符串前面的这个b字符是什么意思? 使用它有什么影响? 什么是适当的情况下使用它? 我在SO上发现了一个相关的问题,但是这个问题与PHP相关,并且它指出b用于表示字符串是二进制的,而不是Unicode,这是代码与PHP版本兼容所需的< 6,迁移到PHP 6.我不认为这适用于Python。 我在Python网站上找到了关于在相同语法中使用u字符来指定字符串为Unicode

Is it pythonic for a function to return multiple values?

In python, you can have a function return multiple values. Here's a contrived example: def divide(x, y): quotient = x/y remainder = x % y return quotient, remainder (q, r) = divide(22, 7) This seems very useful, but it looks like it can also be abused ("Well..function X already computes what we need as an intermediate value. Let's have X return that value also"

函数返回多个值是pythonic吗?

在Python中,你可以有一个函数返回多个值。 这是一个人为的例子: def divide(x, y): quotient = x/y remainder = x % y return quotient, remainder (q, r) = divide(22, 7) 这看起来很有用,但它看起来也可能被滥用(“Well..function X已经计算了我们需要的中间值,让我们让X返回该值)”。 何时应该画线并定义一种不同的方法? 绝对(您提供的示例)。 元组是Python中的一等公民 有一个内置函数divm

Extracting beats out of MP3 music with Python

What kind of solutions are there to analyze beats out of MP3 music in Python? The purpose of this would be to use rhythm information to time the keyframes of generated animation, export animation as video file and and mix the video and audio together. Check this: The Echo Nest Remix API # You can manipulate the beats in a song as a native python list beats = audio_file.analysis.beats beats.

用Python提取MP3音乐的节拍

什么样的解决方案可以分析Python中MP3音乐的节奏? 这样做的目的是使用节奏信息来定时生成动画的关键帧,将动画导出为视频文件并将视频和音频混合在一起。 检查这个: Echo Nest Remix API # You can manipulate the beats in a song as a native python list beats = audio_file.analysis.beats beats.reverse()

How to reduce queries in django model has

Here are two example Django models. Pay special attention to the has_pet method. class Person(models.Model): name = models.CharField(max_length=255) def has_pet(self): return bool(self.pets.all().only('id')) class Pet(models.Model): name = models.CharField(max_length=255) owner = models.ForeignKey(Person, blank=True, null=True, related_name="pets") The problem here is

如何减少django模型中的查询

以下是两个示例Django模型。 要特别注意has_pet方法。 class Person(models.Model): name = models.CharField(max_length=255) def has_pet(self): return bool(self.pets.all().only('id')) class Pet(models.Model): name = models.CharField(max_length=255) owner = models.ForeignKey(Person, blank=True, null=True, related_name="pets") 这里的问题是has_pet方法总是生成一个查询。 如果

Hyperlinks without leading and trailing spaces

Is it possible to create hyperlinks without leading and trailing spaces? The following doesn't work: re`Structured`_Text .. _`Structured`: http://docutils.sourceforge.net/docs/user/rst/quickstart.html The reason I'm asking is I'm working with Chinese text. Spaces are not used as word delimiters in Chinese. With the added spaces the text doesn't look well formatted, for examp

超链接没有前导和尾随空格

是否有可能创建没有前导和尾随空格的超链接? 以下不起作用: re`Structured`_Text .. _`Structured`: http://docutils.sourceforge.net/docs/user/rst/quickstart.html 我问的原因是我正在处理中文文本。 空格不能用作中文的单词分隔符。 添加空格时,文本看起来格式不正确,例如: 没有空格就对了。 与 多了空格不好看。 有任何想法吗? 最终这就是我如何摆脱这个问题。 尴尬,但作品: 没有 空格_就对了。

Python get arguments for partial functions

I am looking to do something similar to what was asked here Getting list of parameter names inside python function, but using partial functions. ie. I need to get the possible arguments for a partial function. I can get the keyword arguments using: my_partial_func.keywords but I am currently struggling to get the non-keyword arguments. The inspect module also yields nothing for this particu

Python获取部分函数的参数

我正在寻找类似于这里提到的东西获取python函数中参数名称的列表,但使用部分函数。 即。 我需要获取部分函数的可能参数。 我可以使用以下关键字参数: my_partial_func.keywords 但我目前正在努力获得非关键字参数。 检查模块对于这种特殊情况也不产生任何影响。 任何建议都会很棒。 .args包含传递给部分函数的参数。 如果您想获得原始函数期望的参数,请使用您在.func属性上链接的inspect解决方案。 你可以通过在f

Take screenshots at fixed intervals with Python using threading.Timer

I'm writing a simple GUI application with pyGTK to take desktop screenshots at fixed intervals. To schedule the shots I use the threading.Timer class and to take shots I use os.system calls to scrot. When I click the start taking screenshots button the GlapseMain.startScreenshots method is called. When I click the stop taking screenshot button the GlapseMain.stopScreenshots method is call

使用threading.Timer以固定间隔与Python进行屏幕截图

我正在用pyGTK编写一个简单的GUI应用程序,以固定的时间间隔进行桌面屏幕截图。 为了安排这些镜头,我使用了threading.Timer类并拍摄了镜头,我使用os.system调用scrot。 当我点击开始拍摄截图按钮时,会调用GlapseMain.startScreenshots方法。 当我点击停止截图按钮时,会调用GlapseMain.stopScreenshots方法。 GTK应用程序正在工作,但没有截图,虽然它应该。 当我点击关闭按钮时,它将开始以截然不同的方式进行截图。

When using the Python Interpreter, is the compiler used at all?

In Google's Python Class it reads Python is a dynamic, interpreted (bytecode-compiled) language I know what an interpreter is and know what bytecode is but the two together seem not to fit. After doing some reading it became a bit clearer that basically Python source code is automatically compiled before it is interpreted; but some new questions emerged. When using the Python Interpre

在使用Python解释器时,编译器是否可以使用?

在Google的Python类中它读取 Python是一种动态的解释(字节码编译)语言 我知道一个解释器是什么,并且知道什么是字节码,但是这两者似乎不合适。 在做了一些阅读后,它变得更清晰了,基本上Python源代码在解释之前自动编译; 但出现了一些新问题。 使用Python解释器时不会编译? 如果是这样,什么时候? 例如,如果您只是在命令行输入代码,并且每次按Enter时都会运行代码,那么编译器何时有机会完成其工作? 同样在

compiler vs interpreter ( on basis of construction and design )

After viewing lots of posts about the difference between compilers and interpreters, I'm still not able to figure out the difference in their construction and internal mechanism. The most common difference I read was that a compiler produces a target program which is executable { means machine code as its output } which can run on a system and than be fed with input. Whereas an interpreter

编译器vs解释器(基于构造和设计)

在查看了大量关于编译器和解释器之间差异的文章后,我仍然无法弄清楚它们的构造和内部机制的不同。 我读到的最常见的区别是,编译器生成一个可执行的目标程序(意味着机器代码作为它的输出),它可以在系统上运行并且不会被输入。 而解释器只是逐行运行输入(这里发生了什么?)并生成输出。 我主要怀疑的是: 1)编译器由词法分析器,解析器,中间代码生成器和代码生成器组成,但是解释器的组成部分是什么? 2)谁给解

set nginx as proxy for both apache and gunicorn at the same time

I have all my code in django, hence using gunicorn to host django, and using nginx as reverse proxy. I now want to host some PHP files on the same domain (or subdomain) using an nginx server as reverse proxy, and apache server. Is it possible to reverse proxy nginx for 2 different servers? (if gunicorn fails, try apache) i can directly host the php files on apache, but port 80 is taken by n

同时将nginx设置为apache和gunicorn的代理

我在django中拥有所有代码,因此使用gunicorn来托管django,并使用nginx作为反向代理。 我现在想使用nginx服务器作为反向代理和apache服务器在同一个域(或子域)上托管一些PHP文件。 是否有可能为2台不同的服务器反向代理服务器nginx? (如果gunicorn失败,请尝试apache) 我可以直接在Apache上托管php文件,但端口80由nginx提取。 比方说,我想主办一个基于PHP的博客应用程序 - WordPress的博客.XXXX.com使用Apache?