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Python creating a dictionary of lists
...
You can use defaultdict:
>>> from collections import defaultdict
>>> d = defaultdict(list)
>>> a = ['1', '2']
>>> for i in a:
... for j in range(int(i), int(i) + 2):
... d[j].append(i)
...
>>> d
defaultdict(<t...
What does character set and collation mean exactly?
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From MySQL docs:
A character set is a set of symbols
and encodings. A collation is a set of
rules for comparing characters in a
character set. Let's make the
distinction clear with an example of
an imaginary ch...
How to check if a variable is a dictionary in Python?
...ery few use-cases in Python that require explicit typechecking - most stem from inheriting a bad implementation to begin with ('god object's, overriding standard library/language constructs, etc.) The original question is itself an XY problem. Why does the OP need to check type? Because according to...
Android Studio: Javadoc is empty on hover
I have moved from Eclipse to Android Studio recently, and am liking it. However, I miss the Javadoc on hover feature from Eclipse.
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How to correctly implement custom iterators and const_iterators?
...fits your container: input, output, forward etc.
Use base iterator classes from standard library. For example, std::iterator with random_access_iterator_tag.These base classes define all type definitions required by STL and do other work.
To avoid code duplication iterator class should be a template...
What is the difference between a route and resource in New Router API?
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Please Note that from 1.11.0 onwards, this.route is only used instead of this.resource. Source: http://guides.emberjs.com/v1.11.0/routing/defining-your-routes/*
Have a look at this post for a detailed explanation.
This is a rough summary...
How to split text without spaces into list of words?
...logarithm of the inverse of the probability to avoid overflows.
The code
from math import log
# Build a cost dictionary, assuming Zipf's law and cost = -math.log(probability).
words = open("words-by-frequency.txt").read().split()
wordcost = dict((k, log((i+1)*log(len(words)))) for i,k in enumerat...
What is the advantage of using forwarding references in range-based for loops?
...This doesn't compile because rvalue vector<bool>::reference returned from the iterator won't bind to a non-const lvalue reference. But this will work:
#include <vector>
int main()
{
std::vector<bool> v(10);
for (auto&& e : v)
e = true;
}
All that being ...
Simulate airplane mode in iPhone Simulator
...like an iPhone. So you need a way, at the system layer, to restrict an app from talking to the network. Unix doesn't provide that; it would almost certainly need kernel support to get it. You could do it more easily for NSURLConnection and its kin, but it could be more confusing if some calls work a...
rsync error: failed to set times on “/foo/bar”: Operation not permitted
I'm getting a confusing error from rsync and the initial things I'm finding from web searches (as well as all the usual chmod'ing) are not solving it:
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