Python is a dynamic, high-level language. Its design focuses on clear syntax, an intuitive approach to object-oriented programming, and making the right way to do things obvious. Python supports modules, exceptions, had an extensive standard module library. Python can also be embedded in other ...

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What can C++ do that Python cannot? [closed]

I was reading this post: http://www.quora.com/What-are-the-advantages-of-Python-over-C++ And I am wondering the converse of this question: what can C++ do that Python cannot? For example, in the ...
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1answer
122 views

Should I use a class as a wrapper?

Lets say I have a class representing a chemical compound class Compound(networkx.Graph): def __init__(self): super(Compound, self).__init__() And lets say that I want to add some ...
3
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4answers
433 views

What argument passing mechanism does python use, and where is this officially documented?

As far as I am aware, python is generally referred to as 'call-by-sharing', but does it implement this with call-by-value (like Java) or call-by-reference? or something else? I would appreciate if ...
3
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6answers
662 views

Why is python treated as a interpreted language when it has a compiling stage? [closed]

Why is that python is treated as only an interpreted language when there is in fact a compiling stage where the code we write gets converted into byte code(.pyc), which is later interpreted by the ...
6
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0answers
154 views

Which languages have the best support for stackful coroutines? [closed]

Various languages support (some flavor of) coroutines. One way to discriminate coroutines is whether they are stackful or not (terminology based on Ana Lucia de Moura; Roberto Ierusalimschy (2004). ...
0
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1answer
48 views

Django Project Logic Solution

I'm starting to develop my first webapp, and I'm using django. Before anything I'm working on the software logic, how it should work, the links and objects it needs. The problem is: I need the app ...
3
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0answers
70 views

auto update strategy for a software distributed as a tar ball written in python 2.7 targeting mac osx

This is what I have planned as an auto update strategy for a software that is as a tar ball. The application is running as a system daemon which means it have root privilege. App runs on startup ...
0
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1answer
60 views

how python updates references to variables

For this while loop below. It is clear how the v1,v2,v3 are updated to new data objects based on the equation. But I do not understand how u1,u2,u3 retains the original values of v1,v2,v3.Can someone ...
2
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1answer
293 views

how to test a generator with unittest?

I have programmed a small iterator in Python: class anything(): def __init__(self): self.i=1 def __iter__(self): return self def next(self): if self.i>100: ...
2
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2answers
148 views

Naming self or this something else, a good idea?

I'm finding that my code becomes more readable when I make a local reference to this/self, and/or call it something that makes sense in the context. "self" or "this" doesn't really indicate what kind ...
1
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2answers
161 views

Python: Object initialised inside a Class?

Is possible and, if so, common practice to initialize an object inside a class in Python? self.field = Class()
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2answers
2k views

Every function is a closure?

Wikipedia says, that closure - is a function, which has an access to variables, declared outside of the function. There is even an example: function startAt(x) function incrementBy(y) ...
0
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1answer
90 views

Handling the process of large-scale lists [closed]

What are the efficient ways to process huge lists (+10 millions), and things to consider while manipulating huge lists. First question, when should I use recursion, and when I shouldn't. In both ...
1
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2answers
122 views

How to handle configuration of Python modules, especially when used standalone and in frameworks like Django

I am trying to package a Python module for pip, following the guide here. One area I would like feedback on is best practices or convention for making my module configurable. The module is a library ...
1
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1answer
66 views

Is this type of data insertion safe and can stop sql injection in Python?

I am learning Database connection from MySQL Connector/Python Developer Guide. This is the code I am using to insert data: conn = mysql.connector.connect(user="user", password="password", ...
1
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1answer
140 views

Why is a python package more perfomant as zip?

I have read the following text in the setuptools documentation: For maximum performance, Python packages are best installed as zip files. ...
0
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1answer
125 views

How do different technologies connect to form a web stack? [closed]

I am a little confused, is it possible to implement a front end using common languages like html, css and javascript and then do server side processing using a language of your choice, say python or ...
2
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0answers
129 views

The Python module-as-singleton hack

I've seen (and once used) this idiom a few times in Python: # At the end of a module: if __name__ == '__main__': main() # or whatever your entry point looks like, this line isn't important else: ...
1
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2answers
928 views

Is it safe to catch ImportError when trying to import optional modules?

I usually see this pattern at least once in every Python project I work on. For example, in a Django project, this is often added at the bottom of the base settings file: try: from .local_settings ...
0
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3answers
271 views

Socket Connecting to Large number of IPs

I have a text file of ~600 CIDR notation IP blocks which, when expanded, amount to ~17.5M IP addresses. I need to socket connect to each one. If it connects, I add it to a "live" list, if it returns ...
4
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2answers
233 views

In Python, is there any difference (apart from a few listed exceptions) between classes and dictionaries?

My logic goes like this: def A(val): return {'a':val} print(A(7)['a']) is the same as class A: def __init__(self, val): self.a = val print(A(7).a) Obviously, there are problems ...
24
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3answers
3k views

Should I pass in filenames to be opened, or open files?

Suppose I have a function that does things with a text file - for example reads from it and removes the word 'a'. I could either pass it a filename and handle the opening/closing in the function, or ...
0
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2answers
311 views

Print Statements Inside Function Or Before Calling It? [closed]

I have a script which different people may use. I have print statements so people can follow along what the script is doing, and if it breaks where it went wrong, and if a certain step takes a long ...
2
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0answers
87 views

How should private dependency links be handled in setup.py

At work we use a private pypi server. This pypi server is specified as a dependency link: ... from setuptools import setup config = ConfigParser.ConfigParser() rc = ...
1
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2answers
160 views

using one database connection across multiple functions in python

whats the best way to go about this in python? I have a number of like so def test1() .... code ..... def test2() .... code ..... def test3() .... code ..... how could I create one ...
0
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3answers
128 views

OOP: relying on protected properties in a class-subclass contract

I'm coding in Python, but the question seems independent of programming language. I have a class that represents some system check: class Check: @abstractmethod def run() """ You have to ...
1
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1answer
100 views

graph implementation in PYthon

I have found the following implementation of a Flow algorithm in Python: class Edge(object): def __init__(self, u, v, w): self.source = u self.sink = v self.capacity = w ...
1
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1answer
529 views

Is there a canonical way to cache instance methods in python?

I have some computationally intensive functions in my python script that I would like to cache. I went looking for solutions on stack overflow and found lots of links: ...
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votes
1answer
91 views

Understanding searching through dicts in python [closed]

I'm trying to understand the differences between dict, dict.items and dict.iteritems. I know that items returns a list of all the items, while iteritems returns an iterator, which for large lists can ...
0
votes
1answer
72 views

No repeated coordinates in random walker ensemble

i'm simulating an ensemble of random walkers in 2D in python, I set [x,y] coordinates of my walkers to be gaussian in a 2D grid, then use a rand array of -1 and +1 to move up down left right: N=20 ...
2
votes
3answers
262 views

How much should I break up my unit tests?

I recently learned about unit tests and TDD and have started going back to add unit tests to my code (and thank god, it's proven that some things I've written are much more broken than I thought). ...
1
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1answer
215 views

Should I couple these classes?

I am programming in Python. I have several complicated/hard-to-understand XML files that describe the structure of an election. I am trying to write a python wrapper that makes it easy to access this ...
1
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1answer
185 views

Transferring information between a web server and a Python backend?

I have been Googling my problem but haven't been able to come up with anything; here's the situation: I have a PHP / MySQL website hosted with 1and1.com. I also have a Python program that runs on a ...
0
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1answer
41 views

Plugins and exporting an API between python scripts

I've got a python script, which should read a subdirectory and make all the scripts within it callable like this: python mainscript.py subscript arguments I've figured out most of the details but ...
1
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2answers
365 views

How-To: a browser based, real time, shared memory inspection/debugger application [closed]

Background: I have a C application running under Linux utilizing shared memory. I also have a debugger written in Python that can link to said shared memory and access individual variable values of ...
2
votes
0answers
146 views

Breaking a table over multiple lines in Sphinx [closed]

Lets say I have the following function with a docstring: def foo(*args): """ do some fooness +----------------------------+----------------------------------------------------+ | ...
2
votes
1answer
159 views

What exactly is this Python statement doing?

I'm trying to port a very basic dual contouring algorithm written in Python (here) to C++. I'm not a Python programmer so some of the language syntax is a bit foreign to me. Specifically, this block ...
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2answers
57 views

How to perform deferred tasks in backend [closed]

Actually the problem is very common. Let me describe this by example. Imagine you have a web service where users register and pay for some gold status. There is expiration date. The question is how to ...
2
votes
4answers
2k views

How to clean up nested try/except/else?

When writing code, I often want to do something like this: try: foo() except FooError: handle_foo() else: try: bar() except BarError: handle_bar() else: ...
3
votes
1answer
158 views

Seeking Guidance on Thread Safe Scripting

I am trying to write a script that will take multiple paths to files on various servers, search them all simultaneously, and return a single list of results to a user. Initially, I was just using ...
0
votes
0answers
35 views

Advice on which approach to follow for sandboxing the input in an intentional “vulnerable” web app (sandbox in python) [duplicate]

my question is about which is the best approach/practice on building a "sandbox mechanism" in Python in a web application. The app will provide intentional vulnerable scenarios, and the user has to ...
4
votes
3answers
555 views

How to avoid large function arity / exposure of underlying implementation

Currently reading Clean Code, and the authors seem to imply that any function with an arity greater than 3 should be avoided at all costs. I am unfortunately running into an issue where I am faced ...
0
votes
2answers
193 views

Prime symbol in Python variable name

So I'm a terrible person and I want to name a variable in my mathy-python3 code s′ (that's a prime symbol). I was under the impression Unicode literals work as identifiers in Python 3, which is why ...
1
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1answer
96 views

Is there a cleaner way to test extras_require

I have code reviewed a piece of Python code, but to me it looks really ugly, hacky and complex for something that can be achieved very easily. The code looks something similar to the following: ...
1
vote
2answers
130 views

Function has two sets of arguments, the latter of which calls a nested function? [closed]

The function foo, has a nested function; bar. Calling foo with a second set of arguments feeds them into bar if bar is returned at the end of foo. How does this work and what is it called? Are there ...
0
votes
1answer
231 views

Is there a way to prevent variables from changing their type in Python?

It is useful to have the interpreter derive the type of a variable automatically. This on its own is similar to the auto keyword in C++11. However, in Python variables can change their type after ...
0
votes
1answer
127 views

Functional dependencies diagram

I'm searching for the correct type of diagram in which I can see all dependencies between the functions, classes and files of my Python program (multiple files). It's for cleaning purposes. So my ...
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votes
1answer
238 views

Base Class, with method that returns Derived Class. design flaw?

I'm writing a Math equation solver in python (for fun). The first design that came to my mind: Expression: base class for every item in an equation (maybe bad name). BinaryExpression extends ...
3
votes
3answers
1k views

Lambda expressions with no parameters in Haskell and / or lambda calculus

In eager languages like Scheme and Python, you can use a lambda expression without parameters to delay evaluation, e.g. in Scheme (Chicken Scheme): #;1> (define (make-thunk x) (lambda () (+ x 1))) ...
0
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1answer
72 views

Should instance variables be bound to the instance right in the beginning of the method they are created in?

A common problem for me - and it's not really a problem, but somehow I again and again ask myself, what is the normal way to handle this - is that there is a method and within this method a couple of ...