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Dynamic cell width of UICollectionView depending on label width
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You cannot imagine how I thank you! That really works. Now I only need to resolve [cell.myLabel sizeToFit] problem, because it appears in its full size only after scrolling. But I have not been even close to your solution.
– pulp
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What is the best algorithm for overriding GetHashCode?
...hroughout the .NET base class libraries. Implementing it properly is especially important to find items quickly in a collection or when determining equality.
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Principal component analysis in Python
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Months later, here's a small class PCA, and a picture:
#!/usr/bin/env python
""" a small class for Principal Component Analysis
Usage:
p = PCA( A, fraction=0.90 )
In:
A: an array of e.g. 1000 observations x 20 variables, 1000 rows x 20 colum...
How to efficiently compare two unordered lists (not sets) in Python?
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For short lists, big-O analysis is usually irrelevant because the timings are dominated by constant factors. For the longer lists, I suspect something is wrong with your benchmarking. For 100 ints with 5 repeats each, I get: 127 usec for sorted and 42 for Count...
Converting between datetime, Timestamp and datetime64
...>> numpy.__version__
'1.6.2' # current version available via pip install numpy
I can reproduce the long value on numpy-1.8.0 installed as:
pip install git+https://github.com/numpy/numpy.git#egg=numpy-dev
The same example:
>>> from datetime import datetime
>>> import num...
How do I list all cron jobs for all users?
Is there a command or an existing script that will let me view all of a *NIX system's scheduled cron jobs at once? I'd like it to include all of the user crontabs, as well as /etc/crontab , and whatever's in /etc/cron.d . It would also be nice to see the specific commands run by run-parts in /e...
What is the difference between a definition and a declaration?
...// extern can be omitted for function declarations
class foo; // no extern allowed for type declarations
A definition actually instantiates/implements this identifier. It's what the linker needs in order to link references to those entities. These are definitions corresponding to the above declara...
Accessing Object Memory Address
When you call the object.__repr__() method in Python you get something like this back:
9 Answers
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How is Math.Pow() implemented in .NET Framework?
...rsion from Henry Warren's Hacker's Delight:
public static int iexp(int a, uint b) {
int y = 1;
while(true) {
if ((b & 1) != 0) y = a*y;
b = b >> 1;
if (b == 0) return y;
a *= a;
}
}
He notes that this operation is optimal (does the minimu...
How to achieve function overloading in C?
...sociation list that looks a bit like a switch block. _Generic gets the overall type of the expression and then "switches" on it to select the end result expression in the list for its type:
_Generic(1, float: 2.0,
char *: "2",
int: 2,
default: get_two_object());
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