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 ...

learn more… | top users | synonyms (1)

0
votes
1answer
45 views

Python shelve class rename

The main reason I use Shelve is to be able to quickly develop code without worrying about db table structure. Unfortunately changing a class name from, say, 'class1' to 'class2' gives "AttributeError: ...
-3
votes
1answer
239 views

Sqlite3 slow on standard queries, is it expected? [closed]

Using Python and sqlite3. This simple print loop takes a few seconds to execute. I don't know much about databases, so I'm guessing I'm not using these queries correctly. Surely sqlite should be ...
3
votes
3answers
174 views

Unit Testing: How much more code? [duplicate]

I'm fairly new to unit testing. In school it's always been, "hey it works, onward!" But I've started to write professionally, and even at work that's been basically the mantra. However, I've started ...
4
votes
2answers
267 views

Should duck typing affect naming conventions?

I'm a C++/C# developer and recently I've started to learn Python. I think I understand the concept of duck typing right now except for one thing. When I'm coding in C++ or C# I sometimes create ...
29
votes
1answer
1k views

How to deal with a misnamed function in production code?

I've recently come across a Python library on GitHub. The library is great, but contains one glaring typo in a function name. Let's call it dummy_fuction() while it should be dummy_function(). This ...
0
votes
1answer
144 views

Is the following example a strategy pattern?

In my problem I had lots of objects with slightly different behaviour, but identical attributes and methodes with identical interfaces. The objects variants were quite big in number, and I didn't want ...
3
votes
0answers
266 views

Why are so many Python files really big (5k+ lines)? [closed]

Is there any specific reason driving Python files to often be so large? Python files may contain several classes within one file, and some files go up over 10k lines in length. This seems to go ...
4
votes
2answers
293 views

Using a closure to avoid code duplication in Python

Sometimes I find myself wanting to run the same code from a few different spots in the same function. Say I have some function func1, and I want to do the same thing from a few different spots in ...
1
vote
0answers
159 views

Gevent - Make blocking calls non-blocking

I have the blocking code shown below. Is calling monkey.patch_all() enough/optimal to make it non-blocking? Does Gevent handle iterations like these? # front page def front_page(): database = ...
-3
votes
1answer
195 views

Is there a purely technical term for 'monkey patching' [closed]

EDIT The original title of the question was Is there a non-derogatory term for 'monkey patching'. As I have learned that the term is actually not derogatory, or is at least not meant to be, I changed ...
1
vote
1answer
92 views

Is it possible to get probabilities from a support vector machine?

From what I understand, SVM's take a discrete number of x and y values from which to learn from, then when given new x values map it to one y value (category). Is it possible to use SVM's or something ...
14
votes
2answers
793 views

Creating nested functions for purely aesthetic reasons?

I've always wondered what other programmers think about the idea of creating pure aesthetic functions. Say I have a function that processes a chunk of data: Function ProcessBigData. Say I need ...
0
votes
0answers
74 views

streaming data in memory aggregation

We have a stream of data we're aggregating stats over and putting into a python dictionary (sent from kafka). Every X time interval, We update our database with these aggregated metrics. This ...
0
votes
2answers
742 views

DDD - Domain Driven Design, which development order should be applied?

1 - Design my entities, ie (in python): class Account: def __init__(name, author): self.name = name self.email = email 2 - Design my repositories: (as interface) class ...
4
votes
2answers
2k views

Why does Python use hash table to implement dict, but not Red-Black Tree? [closed]

Why does Python use hash table to implement dict, but not Red-Black Tree? What is the key? Performance?
3
votes
2answers
563 views

Why do concurrent languages tend to have more complicated syntax?

This is a question that's been on my mind for a while. Recently I've been checking out concurrent languages like Haskell or Go or Erlang. From my point of view, they have huge benefit in performance ...
2
votes
1answer
226 views

Python - Is this a bad strategy pattern?

I've got a Python project wherein a basic object is created and various different attributes are modified/given to it via what I thought was a good example of a strategy pattern. In this silly game ...
0
votes
0answers
144 views

subclass QAbstractTableModel - reuse as much code as possible

in my PyQt application I am heavily using the model/view approach. For every model I create, I do the following: class myModel(QtCore.QAbstractTableModel): def __init__(self, parent = None): ...
1
vote
1answer
109 views

Best way to search through directory structure

I'm working on a python program which organizes a music library. The program will basically help me detect misspelled file or directory names, wrong FLAC tags or unknown/superfluous files. It will ...
0
votes
1answer
124 views

scipy.stats.percentileofscore() wrong?

i'm a data scientist and python noob, but I seem to have found a bug with scipy.stats.percentileofscore. it may be "by design" but please bear with me. if you have an array, you will get an upper ...
0
votes
2answers
236 views

Python - only one return per method? [duplicate]

I'm trying to sort out whether this is just a personal preference thing or whether it's actually bad practice to do this one way or another. I did try to reference PEP8 first, and I did not see an ...
5
votes
2answers
327 views

Is there a name for the number of values a variable can take? [closed]

For example, a bit or a boolean can be either 0 or 1 so the number 2 is associated with it. Similarly, for a byte which is 8 bits, the maximum number of different assignments would be 2^8. Is there a ...
0
votes
3answers
410 views

Isolating unit tests in python

As a 30-year software developer, mostly in OO languages, but a newbie at python, I'm looking to find what is best practise for isolating unit tests in python. Let's say I have the following, ...
3
votes
2answers
225 views

Tablet development for a dedicated system

I need to make an architectural decision for developing (actually porting) my embedded solution on a tablet. The choice comes down to Ubuntu or Android, so I have some specific questions to help me ...
2
votes
1answer
131 views

why is len not a reserved keyword in python

why is functions like len and max not a reserved keyword in python. Following are the only reserved words http://docs.python.org/2/reference/lexical_analysis.html#keywords
2
votes
3answers
156 views

When to use python function nesting?

I am writing a program that creates backup of directories. Which of the following approach is better for code organization? Create separate class for Backup and Zip logic - class BackupUtil: ...
0
votes
1answer
186 views

How to Think like a computer Scientist. Chapter 3, Question 2 [closed]

http://interactivepython.org/runestone/static/thinkcspy/PythonTurtle/helloturtle.html I'm stuck on question 3. Give three attributes of your cellphone object. Give three methods of your cellphone. ...
0
votes
1answer
118 views

Making a sldprt to PDB file converter?

I wanted to create a parser that can read a solidworks file and turn it into a protein data bank file. This has already been done in a program called DiamondCAD. ...
0
votes
3answers
215 views

Is it possible to have setup and tear down methods run only for specific unittests?

I currently have a test class with a setUp method for creating a temp file and a tearDown method for deleting a temp file. However, only some of the the test_ methods in that class require this ...
0
votes
1answer
391 views

How to develop an algorithm for brute-forcing / backtracking?

As a beginner programmer, I don't know how to conceptually think about brute-forcing. My mind can't really fathom how to write code that will try every possibility. I have a problem that I want to ...
2
votes
3answers
573 views

Global request context - anti-pattern?

I was talking today to a colleague of mine about Python web frameworks and our impressions about them. I told him I think Flask having a global request smells badly and is an anti-pattern. The docs ...
0
votes
0answers
77 views

Check some value between each function call

Can you recommend a nice way of checking a particular value between calls to a set of functions? E.g. something like this in Python (might not be terribly 'Pythonic'): self.error_code = 0 # this ...
3
votes
1answer
199 views

Advantages of contracts over assert statements

Today I stumbled upon the python package called PyContracts. However, python has the assert statement which seems to allow you to do exactly those things. What advantages do contracts have over assert ...
10
votes
2answers
5k views

Is it conventional to raise a NotImplementedError for methods whose implementation is pending, but not planned to be abstract?

I like to raise a NotImplementedError for any method that I want to implement, but where I haven't gotten around to doing it yet. I might already have a partial implementation, but prepend it with ...
1
vote
3answers
207 views

Python methods vs builtin functions

Python widely uses built-ins (or module function) and not class methods. So len([]) instead of [].length() filter(f, []) instead of [].filter(f) str(2) instead of 2.to_str same for map, foreach etc ...
0
votes
3answers
56 views

If an object should be flagged, should it be built with the flag attribute?

Let us assume I have a basic object with a handful of self-relevant points of data. class A(object): def __init__(self, x, y, width, length): self.x = x self.y = x ...
-2
votes
2answers
131 views

RESTful API development : is it web developer's work or software developer's work? [closed]

First of all, I am sorry that the issue I'm going to say is not about a technical thing. I'm just confused. I am trying applying to several companies as a software engineer. The latest work that I ...
1
vote
1answer
502 views

Logging in a distributed system

We have several application servers (and different applications) running on Amazon AWS and our main method of logging is a combination of statsd, carbon/graphite, and an alert system based off of the ...
1
vote
1answer
178 views

Pythonic version of Java interfaces

I fully acknowledge that Python and Java are different programming languages and should be used differently. That said, "Program to an interface, not to an implementation" is good language-agnostic ...
1
vote
2answers
329 views

Usage of __ while declaring any variables or class member in python

Is it good practice to use __ convention while declaring the member variable? This also imparts private kind of feature of that data member. There have been cases when I found that its good to have ...
1
vote
2answers
90 views

Learning python functions and parameters

def printMax(a, b): if a > b: print(a, 'is maximum') elif a == b: print(a, 'is equal to', b) else: print(b, 'is maximum') printMax(3, 4) # directly give literal values x = 5 y = ...
10
votes
9answers
2k views

Is there any difference learning OOP on different programming languages? [closed]

I want to learn OOP. I know Python and I know very little things about OOP. But when I search for "learn OOP" in forums I saw a guy saying that "Python is so new that's why you can't learn OOP on ...
1
vote
1answer
123 views

Why chaining matters (Python & SQLite3)?

Why does cursor = connection.cursor() cursor.execute("... return cursor.fetchall() return the expected non-empty result whereas connection.cursor().execute("... return ...
0
votes
1answer
156 views

does anyone know how to use the PyQt 'uic' module method 'compileUiDir'?

I don't find the docstring to be very clear: def compileUiDir(dir, recurse=False, map=None, **compileUi_args): """compileUiDir(dir, recurse=False, map=None, **compileUi_args) Creates Python ...
1
vote
2answers
517 views

Python sorted iterable set, modifiable during iteration

I am looking for a datastructure to handle cycling through a large number of ordered subroutines, some of which are active, most of which are not. I am thinking I need an implementation of a python ...
0
votes
1answer
80 views

Pythonic design for controlling multiple devices through an I2C bus

I'm writing a piece of software in python that will communicate with a bunch of devices via an I2C bus. Each of these devices are going to need some sort of a module or class to handle the ...
1
vote
1answer
160 views

Dynamic method creation in python

I have a class that will have a number of external methods that will all call the same smaller set of internal methods. So something like: obj.method_one(a, c) and obj.method_two(a, c) where ...
0
votes
1answer
180 views

In python, do we have class encapsulation at the level of the object?

I was bitten by using the is operator when i should have been using ==. Am aware that the former tests for equality of the objects' identities and that the latter tests for equality of the objects' ...
0
votes
1answer
550 views

Using module level declared global “singletons” in python

Ok, I know that using singletons is generally a bad practice, but if I do it (for db connection, logging et al.) am I allowed to go (in respect of clean design) with a module defined variable that is ...
0
votes
2answers
2k views

How to write an optimal LAN messenger software?

I am asking this question as an extension to the following question: https://superuser.com/questions/713409/how-to-message-any-user-on-your-lan I don't think I have a real answer. I found it quite ...