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Generate a random point within a circle (uniformly)
I need to generate a uniformly random point within a circle of radius R .
21 Answers
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Why doesn't Java Map extend Collection?
...doesn't Map extend Collection?
This was by design. We feel that
mappings are not collections and
collections are not mappings. Thus, it
makes little sense for Map to extend
the Collection interface (or vice
versa).
If a Map is a Collection, what are the
elements? The only reaso...
Execute code when Django starts ONCE only?
I'm writing a Django Middleware class that I want to execute only once at startup, to initialise some other arbritary code. I've followed the very nice solution posted by sdolan here , but the "Hello" message is output to the terminal twice . E.g.
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How do I capture SIGINT in Python?
I'm working on a python script that starts several processes and database connections. Every now and then I want to kill the script with a Ctrl + C signal, and I'd like to do some cleanup.
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SQLite - UPSERT *not* INSERT or REPLACE
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Assuming three columns in the table: ID, NAME, ROLE
BAD: This will insert or replace all columns with new values for ID=1:
INSERT OR REPLACE INTO Employee (id, name, role)
VALUES (1, 'John Foo', 'CEO');
BAD: This will i...
How do ACID and database transactions work?
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ACID is a set of properties that you would like to apply when modifying a database.
Atomicity
Consistency
Isolation
Durability
A transaction is a set of related changes which is used to achieve some of the ACID properties. Transactions are tools to achieve the ACID properties.
Atomicity ...
Converting integer to string in Python
I want to convert an integer to a string in Python. I am typecasting it in vain:
12 Answers
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read subprocess stdout line by line
My python script uses subprocess to call a linux utility that is very noisy. I want to store all of the output to a log file and show some of it to the user. I thought the following would work, but the output doesn't show up in my application until the utility has produced a significant amount of ...
How do I revert all local changes in Git managed project to previous state?
I have a project in which I ran git init .
After several commits, I did git status which told me everything was up to date and there were no local changes.
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How to define a function in ghci across multiple lines?
I'm trying to define any simple function that spans multiple lines in ghci, take the following as an example:
7 Answers
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