python

Indexing CSV file contents in Python

Hi, I have a very large CSV file contaning only two fields (id,url). I want to do some indexing on the url field with python, I know that there are some tools like Whoosh or Pylucene. but I can't get the examples to work. can someone help me with this? ...

Python __setattr__ and __getattr__ for global scope?

Suppose I need to create my own small DSL that would use Python to describe a certain data structure. E.g. I'd like to be able to write something like f(x) = some_stuff(a,b,c) and have Python, instead of complaining about undeclared identifiers or attempting to invoke the function some_stuff, convert it to a literal expression for my ...

Get and set data on Google App Engine

How can I store some data on Google App Engine? I'm using Django. ...

In MAYA 2009, is it possible to capture the cube rotate event?

I need to call a function ( Maya-Python ) based on cube rotationX. For that I have to capture the event, programmatically. I tried using while loop but It stucks in the loop, Nothing can be done in that time. I tried theading (python), still same. Can it be done this or other way? If yes, How? Maya 2009 in Windows XP Some failed code...

Preserve time stamp when shrinking an image

My digital camera takes pictures with a very high resolution, and I have a PIL script to shrink them to 800x600 (or 600x800). However, it would be nice for the resultant file to retain the original timestamp. I noticed in the docs that I can use a File object instead of a name in PIL's image save method, but I don't know if that will hel...

Attribute References in Python

I do Java programming and recently started learning Python via the official documentation. I see that we can dynamically add data attributes to an instance object unlike in Java: class House: pass my_house = House() my_house.number = 40 my_house.rooms = 8 my_house.garden = 1 My question is, in what situations is this feature used?...

Python Expand Tabs Length Calculation

I'm confused by how the length of a string is calculated when expandtabs is used. I thought expandtabs replaces tabs with the appropriate number of spaces (with the default number of spaces per tab being 8). However, when I ran the commands using strings of varying lengths and varying numbers of tabs, the length calculation was different...

"IronPython + .NET" vs "Python + PyQt". Which one is better for Windows App development?

Hi, I'm new in using Python. I would like to develop Windows GUI Application using Python. After some research, I found that I have 2 options:- IronPython + .NET Framework Python + PyQt May I know which one is better for Windows Application development? Which option has more features (e.g. database support, etc)? Other than the .NE...

Idiomatic Python: 'times' loop

Say I have a function foo that I want to call n times. In Ruby, I would write: n.times { foo } In Python, I could write: for _ in xrange(n): foo() But that seems like a hacky way of doing things. My question: Is there an idiomatic way of doing this in Python? ...

Django admin: Add a "remove file" field for Image- or FileFields

I was hunting around the Internet for a way to easily allow users to blank out imagefield/filefields they have set in the admin. I found this: http://www.djangosnippets.org/snippets/894/. What was really interesting to me here was the code posted in the comment by rfugger: remove_the_file = forms.BooleanField(required=False) def save...

Where can i find good practice python problems with solutions?

Where can i find good practice python problems with solutions? I'm looking for detailed practice problems that are designed with a coding purpose in mind. ...

How to fix this python program?

import math def p(n): return 393000*((288200/393000)^n * math.exp(-(288200/393000)))/math.factorial(n) print p(3) When I run it, I get the following error message: Traceback (most recent call last): File "poisson.py", line 6, in <module> print p(3) File "poisson.py", line 4, in p return 393000*((288200/393000)^n * ma...

Passing sql results to views hard-codes views to database column names

I just realized that i may not be following best practices in regards to the MVC pattern. My issue is that my views "know" information about my database Here's my situation in psuedo code... My controller invokes a method from my model and passes it directly to the view view.records = tableGateway.getRecords() // gets array of record...

Qt: How to autoexpand parents of a new QTreeView item when using a QSortFilterProxyModel

I'm making an app wherein the user can add new data to a QTreeModel at any time. The parent under which it gets placed is automatically expanded to show the new item: self.tree = DiceModel(headers) self.treeView.setModel(self.tree) expand_node = self.tree.addRoll() #addRoll makes a node, adds it, and returns the (parent) note to be expa...

Why does python use 'magic methods'?

I've been playing around with Python recently, and one thing I'm finding a bit odd is the extensive use of 'magic methods', e.g. to make its length available an object implements a method def __len__(self) and then it is called when you write len(obj). I was just wondering why objects don't simply define a len(self) method and have it c...

Insert a newline character every 64 characters using Python

Using Python I need to insert a newline character into a string every 64 characters. In Perl it's easy: s/(.{64})/$1\n/ How could this be done using regular expressions in Python? Is there a more pythonic way to do it? ...

Get localized language name from locale code

How can I get localized language name by specified locale code in python? For example: >> get_language_name('ja') >> ('Japanese', u'日本語') ...

jar to python module

I am using an API which provides a Java version but not a Python version. I can switch to Java as right now I am only prototyping. but is there a quick way to convert the functionality of API packaged in a jar to a python module? ...

How to change the date/time in Python for all modules?

When I write with business logic, my code often depends on the current time. For example the algorithm which looks at each unfinished order and checks if an invoice should be sent (which depends on the no of days since the job was ended). In these cases creating an invoice is not triggered by an explicit user action but by a background j...

how to login in google account with app engine webproxy

hi,a webproxy on app engine oncyberspace.appspot.com , save cookie in the database, when i try to login in the google with my account, it redirect to google.com . how to solve these problem ? and another problem , when i this the above web to login in twitter,it works !but i can not use it to update my tweet. i don't know why, may be i c...