python

Django Image Upload: IOErrno2 Could not find path -- and yet it's saving the image there anyway?

I have an issue where the local version of django is handling image upload as expected but my server is not. Note: I am using a Django Container on MediaTemple.net (grid server) Here is my code. def view_settings(request): <snip> if request.POST: success_msgs = () mForm = MainProfileForm(request.POST, request.FILES, instan...

Python 2D list has weird behavor when trying to modify a single value...

Hi guys, So I am relatively new to Python and I am having trouble working with 2D Lists. Here's my code: data = [[None]*5]*5 data[0][0] = 'Cell A1' print data and here is the output (formatted for readability): [['Cell A1', None, None, None, None], ['Cell A1', None, None, None, None], ['Cell A1', None, None, None, None], ['Cell ...

Condition checking vs. Exception handling

When is exception handling more preferable than condition checking? There are many situations where I can choose using one or the other. For example, this is a summing function which uses a custom exception: # module mylibrary class WrongSummand(Exception): pass def sum_(a, b): """ returns the sum of two summands of the same ...

Extract list of attributes from list of objects in python

Hi, I have an uniform list of objects in python: class myClass(object): def __init__(self, attr): self.attr = attr self.other = None objs = [myClass (i) for i in range(10)] Now I want to extract a list with some attribute of that class (let's say attr), in order to pass it so some function (for plotting that data ...

What causes the Openid error: Received "invalidate_handle" from server

I'm new to openid, and I am getting an "invalidate_handle" and I have no idea what to do to fix it. I'm using django_authopenid [Thu Apr 29 14:13:28 2010] [error] Generated checkid_setup request to https://www.google.com/accounts/o8/ud with assocication AOxxxxxxxxOX5-V9oDc3-btHhFxzAcccccccccc2RTHgh [Thu Apr 29 14:13:29 2010] [error]...

Could somebody give me a high-level technical overview of WSGI details behind the scenes vs other web interface approaces with Python?

Firstly: I understand what WSGI is and how to use it I understand what "other" methods (Apache mod-python, fcgi, et al) are, and how to use them I understand their practical differences What I don't understand is how each of the various "other" methods work compared to something like UWSGI, behind the scenes. Does your server (Nginx,...

Qt gstreamer problem

Ptterb can you post your full code please? I copied your code. Added fvidscale_cap to pipeline, with: self.player.add(self.source, self.scaler, self.fvidscale_cap, self.sink) gst.element_link_many(self.source,self.scaler, self.fvidscale_cap, self.sink) From the main program I create a new QWidget, and pass its winId() to Vid construc...

Reading numeric Excel data as text using xlrd in Python

Hi guys, I am trying to read in an Excel file using xlrd, and I am wondering if there is a way to ignore the cell formatting used in Excel file, and just import all data as text? Here is the code I am using for far: import xlrd xls_file = 'xltest.xls' xls_workbook = xlrd.open_workbook(xls_file) xls_sheet = xls_workbook.sheet_by_index...

Why are filename underscores better than hyphens

From Building Skills in Python: "A file name like exercise_1.py is better than the name execise-1.py. We can run both programs equally well from the command line, but the name with the hyphen limits our ability to write larger and more sophisticated programs." Why? ...

Python raises a KeyError (for an out of dictionary key) even though the key IS in the dictionary

I'm getting a KeyError for an out of dictionary key, even though I know the key IS in fact in the dictionary. Any ideas as to what might be causing this? print G.keys() returns the following: ['24', '25', '20', '21', '22', '23', '1', '3', '2', '5', '4', '7', '6', '9', '8', '11', '10', '13', '12', '15', '14', '17', '16', '19', '18'] ...

Are there some cases where Python threads can safely manipulate shared state?

Some discussion in another question has encouraged me to to better understand cases where locking is required in multithreaded Python programs. Per this article on threading in Python, I have several solid, testable examples of pitfalls that can occur when multiple threads access shared state. The example race condition provided on thi...

Email attachment problem

Hi there, I want to send an email with an attachment using the following code (Python 3.1) (greatly simplified to show the example) from email.mime.multipart import MIMEMultipart from email.mime.text import MIMEText msg = MIMEMultipart() msg['From'] = from_addr msg['To'] = to_addr msg['Subject'] = subject msg.attach(MIMEText(body)) f...

How do you read a cell's value from an OpenOffice Calc .ods file with python?

I have been able to read an excel cell value with xlrd using column and row numbers as inputs. Now I need to access the same cell values in some spreadsheets that were saved in .ods format. So for example, how would I read the value stored in cell E10 from a .ods file from python? ...

Issue with python string join.

I have some code in which I apply a join to a list. The list before the join looks like this: ["'DealerwebAgcy_NYK_GW_UAT'", "'DealerwebAgcy'", "'UAT'", '@ECNPhysicalMarketCo nfigId', "'GATEWAY'", "'DEALERWEB_MD_AGCY'", "'NU1MKVETC'", "'mkvetcu'", "'C:\te mp'", '0', "'NYK'", '0', '1', "'isqlw.exe'", 'GetDate()', '12345', "'NYK'",...

Python SQLite: database is locked

I'm trying this code: import sqlite connection = sqlite.connect('cache.db') cur = connection.cursor() cur.execute('''create table item (id integer primary key, itemno text unique, scancode text, descr text, price real)''') connection.commit() cur.close() I'm catching this exception: Traceback (most recent call last): Fi...

Which Python API should be used with Mongo DB and Django

I have been going back and forth over which Python API to use when interacting with Mongo. I did a quick survey of the landscape and identified three leading candidates. PyMongo MongoEngine Ming If you were designing a new content-heavy website using the django framework, what API would you choose and why? MongoEngine looks like i...

Simulating C-style for loops in python

(even the title of this is going to cause flames, I realize) Python made the deliberate design choice to have the for loop use explicit iterables, with the benefit of considerably simplified code in most cases. However, sometimes it is quite a pain to construct an iterable if your test case and update function are complicated, and so...

Python repl in python application

Hello i am learning python(so i can use qt with python not only c++) and i'm curios if it would be possible to embed a python interpreter in my application as a repl. I would like to give users to possibility to script the app using python either loading a file (and that file to act as a plugin for the app) or by evaluating code entered ...

Python: pyximporting a pyx that depends on a native library

My pyx depends upon a native library How can I pyximport.install() it? The auto-build in pyxinstall doesn't know to link with the native library, so the build fails... ...

Scraping *.aspx content using Python

I'm having difficulties scraping dynamically generated table in ASPX. Trying to scrape the gas prices from a site like this GasPrices. I can extract all the information in the gas price table (address, time submitted etc.), except for the actual gas price. Is there a way I could scrape the gas prices? i.e. somehow get a text representa...