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How to safely open/close files in python 2.4
...python.org:
When you’re done with a file, call f.close() to close it and free up any system resources taken up by the open file. After calling f.close(), attempts to use the file object will automatically fail.
Hence use close() elegantly with try/finally:
f = open('file.txt', 'r')
try:
...
How can I map True/False to 1/0 in a Pandas DataFrame?
I have a column in python pandas DataFrame that has boolean True/False values, but for further calculations I need 1/0 representation. Is there a quick pandas/numpy way to do that?
...
Loop through properties in JavaScript object with Lodash
...
Yes you can and lodash is not needed... i.e.
for (var key in myObject.options) {
// check also if property is not inherited from prototype
if (myObject.options.hasOwnProperty(key)) {
var value = myObject.options[key];
}
}
E...
Using comparison operators in Scala's pattern matching system
...
You can add a guard, i.e. an if and a boolean expression after the pattern:
a match {
case 10 => println("ten")
case x if x > 10 => println("greater than ten")
case _ => println("less than ten")
}
Edit: Note that this is more than...
Float vs Decimal in ActiveRecord
...ation defines floats in binary format. Basically, it stores sign, fraction and exponent to represent a Float. It's like a scientific notation for binary (something like +1.43*10^2). Because of that, it is impossible to store fractions and decimals in Float exactly.
That's why there is a Decimal for...
Sharing a result queue among several processes
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Try using multiprocessing.Manager to manage your queue and to also make it accessible to different workers.
import multiprocessing
def worker(name, que):
que.put("%d is done" % name)
if __name__ == '__main__':
pool = multiprocessing.Pool(processes=3)
m = multiproces...
How do I explicitly instantiate a template function?
...T] There seems to be (a lot) of confusion regarding explicit instantiation and specialization.
The code I posted above deals with explicit instantiation. The syntax for specialization is different.
Here is syntax for specialization:
template <typename T> void func(T param) {} // definition
t...
Where is the syntax for TypeScript comments documented?
...ther documentation tools.
A good overview of the syntax is available here and especially here. The precise spec should be "soon" written up.
Another file worth checking out is this one where you will see useful standard tags.
Note: you should not use JSDoc, as explained on TSDoc main page: Why ca...
How do I call setattr() on the current module?
... scope it's called at: the module's variables when called at global scope, and then it's OK to use it R/W, but the function's variables when called in a function, and then it must be treated as R/O -- the Python online docs can be a bit confusing about this specific distinction).
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What's wrong with foreign keys?
...ber correctly). However, to me they seem pretty vital to avoid duplication and subsequent data integrity problems throughout your database.
...