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Why 0 is true but false is 1 in the shell?
...failure - why it happened, how to fix it, etc. Having zero mean 'success' and non-zero mean failure lets you can check pretty easily for success, and investigate the particular error for more details if you want to. A lot of APIs and frameworks have a similar convention - functions that succeed re...
When would anyone use a union? Is it a remnant from the C-only days?
...pace to work with, or when you're developing an API (or something similar) and you want to force the end user to have only one instance of several objects/types at one time. Are these two guesses even close to right?
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Why is SSE scalar sqrt(x) slower than rsqrt(x) * x?
I've been profiling some of our core math on an Intel Core Duo, and while looking at various approaches to square root I've noticed something odd: using the SSE scalar operations, it is faster to take a reciprocal square root and multiply it to get the sqrt, than it is to use the native sqrt opcode!...
What's the difference between deque and list STL containers?
...e is very much like a vector: like vector, it is a sequence that supports random access to elements, constant time insertion and removal of elements at the end of the sequence, and linear time insertion and removal of elements in the middle.
The main way in which deque differs from vector is that de...
What is the difference between join and merge in Pandas?
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I always use join on indices:
import pandas as pd
left = pd.DataFrame({'key': ['foo', 'bar'], 'val': [1, 2]}).set_index('key')
right = pd.DataFrame({'key': ['foo', 'bar'], 'val': [4, 5]}).set_index('key')
left.join(right, lsuffix='_l', rsuffix='_r')
val_l ...
Saving an Object (Data persistence)
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You could use the pickle module in the standard library.
Here's an elementary application of it to your example:
import pickle
class Company(object):
def __init__(self, name, value):
self.name = name
self.value = value
with open('company_data....
How do I pass a unique_ptr argument to a constructor or a function?
I'm new to move semantics in C++11 and I don't know very well how to handle unique_ptr parameters in constructors or functions. Consider this class referencing itself:
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What is recursion and when should I use it?
One of the topics that seems to come up regularly on mailing lists and online discussions is the merits (or lack thereof) of doing a Computer Science Degree. An argument that seems to come up time and again for the negative party is that they have been coding for some number of years and they have n...
Map enum in JPA with fixed values?
...m using JPA. I especially want to set the integer value of each enum entry and to save only the integer value.
9 Answers
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Overwrite or override
It might seem to be a stupid question but I'm just so curious and want to use the correct term when talking about the issue. Couldn't find a similar question here so I decided to create a new one.
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