I am working on knight’s tour problem, and using backtracking algorithm. My code doesn’t produce the right output in the end it just repeats the last two entries over and over until n^2 -1 is not reached. This is my code. I am following this pseudocode http://www.wou.edu/~broegb/Cs345/KnightTour.p…
Tag: python
Replacing tags of one kind with tags of another in BeautifulSoup
I have a collection of HTML files. I wish to iterate over them, one by one, editing the mark-up of a particular class. The code I wish to edit is of the following form, using the following class names : This can occur multiple times in the same document, with different text instead of “Put me Elsewhere&…
What is the simplest way to retry a Django view upon an exception being raised?
I want to rerun a Django view function if a certain exception is raised (in my case a serialization error in the underlying database). I want it to run with exactly the same parameters, including the same request object – as if the client had re-requested the URL. There are many database queries in the …
how to filter json array in python
That is the current json array I have. I want get all json objects that type=1 before filter: after filter: please help. Answer The following snippet of code does exactly what you want, but BEWARE that your input (as written in the question) is not a valid json string, you can check here: http://jsonlint.com.
Create variable key/value pairs with argparse (python)
I’m using argparse module to set my command line options. I’m also using a dict as a config in my application. Simple key/value store. What I’m looking for is a possibility to override JSON options using command line arguments, without defining all possible arguments in advance. Something li…
Error “QObject::startTimer: QTimer can only be used with threads started with QThread” many times when closing application
I know this has been asked many times before. I read all of those threads, and my case seems different. Everybody else who has this trouble has a few straightforward causes that I think I’ve ruled out, such as: Starting a timer with no event loop running Starting/stopping a timer from a thread other than the …
How do I bin and categorize numbers in Python?
I’m not sure if binning is the correct term, but I want to implement the following for a project I am working on: I have an array or maybe a dict describing boundaries and/or regions, for example: The areas are indexed from 0 to 100 (for example). I want to classify each area into a color (that is less …
Dynamically creating Django models with `type`
I have 20+ MySQL tables, prm_a, prm_b, … with the same basic structure but different names, and I’d like to associate them with Django model classes without writing each one by hand. So, feeling ambitious, I thought I’d try my hand at using type() as a class-factory: The following works: But…
UnicodeEncodeError: ‘charmap’ codec can’t encode characters
I’m trying to scrape a website, but it gives me an error. I’m using the following code: And I’m getting the following error: What can I do to fix this? Answer I fixed it by adding .encode(“utf-8”) to soup. That means that print(soup) becomes print(soup.encode(“utf-8”)…
How to get python default exception message in exception handling
When I handle an exception in python It prints I expect it to print Is there a way to retrieve the default error message ? Answer Instead of this: do this: or just this: