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How can I make pandas dataframe column headers all lowercase?
I want to make all column headers in my pandas data frame lower case
5 Answers
5
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How do you programmatically set an attribute?
Suppose I have a python object x and a string s , how do I set the attribute s on x ? So:
4 Answers
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Check if list contains any of another list
... performing on larger collections would be to project parameters to source and then use Intersect which internally uses a HashSet<T> so instead of O(n^2) for the first approach (the equivalent of two nested loops) you can do the check in O(n) :
bool hasMatch = parameters.Select(x => x.sour...
64-bit version of Boost for 64-bit windows
...As a longer answer, here are my build notes for having VS .NET 2008 32-bit and 64-bit boost libraries in the same hierarchy (which is I suspect a common use case):
Build the win32 binaries
bjam --toolset=msvc-9.0 --build-type=complete stage
Create the directory lib\win32
Move the contents of sta...
How to specialize std::hash::operator() for user-defined type in unordered containers?
To support user-defined key types in std::unordered_set<Key> and std::unordered_map<Key, Value>
one has to provide operator==(Key, Key) and a hash functor:
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Inheriting constructors
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If your compiler supports C++11 standard, there is a constructor inheritance using using (pun intended). For more see Wikipedia C++11 article. You write:
class A
{
public:
explicit A(int x) {}
};
class B: public A
{
using A::A;
};
This i...
What is the apply function in Scala?
I never understood it from the contrived unmarshalling and verbing nouns ( an AddTwo class has an apply that adds two!) examples.
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python numpy ValueError: operands could not be broadcast together with shapes
In numpy, I have two "arrays", X is (m,n) and y is a vector (n,1)
6 Answers
6
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u'\ufeff' in Python string
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The Unicode character U+FEFF is the byte order mark, or BOM, and is used to tell the difference between big- and little-endian UTF-16 encoding. If you decode the web page using the right codec, Python will remove it for you. Examples:
#!python2
#coding: utf8
u = u'ABC'
e8 = u.encode...
What really happens in a try { return x; } finally { x = null; } statement?
I saw this tip in another question and was wondering if someone could explain to me how on earth this works?
5 Answers
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