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C# 5 async CTP: why is internal “state” set to 0 in generated code before EndAwait call?
...t. Many thanks to him - and please visit his blog, which rocks.
The value 0 here is only special because it's not a valid state which you might be in just before the await in a normal case. In particular, it's not a state which the state machine may end up testing for elsewhere. I believe that usin...
What is the most efficient way of finding all the factors of a number in Python?
...(reduce(list.__add__,
([i, n//i] for i in range(1, int(n**0.5) + 1) if n % i == 0)))
This will return all of the factors, very quickly, of a number n.
Why square root as the upper limit?
sqrt(x) * sqrt(x) = x. So if the two factors are the same, they're both the square root. If ...
How to track down a “double free or corruption” error
...
answered May 25 '10 at 8:42
HasturkunHasturkun
31.2k55 gold badges6565 silver badges9595 bronze badges
...
How to count the number of true elements in a NumPy bool array
...xample:
>>> import numpy as np
>>> boolarr = np.array([[0, 0, 1], [1, 0, 1], [1, 0, 1]], dtype=np.bool)
>>> boolarr
array([[False, False, True],
[ True, False, True],
[ True, False, True]], dtype=bool)
>>> np.sum(boolarr)
5
Of course, that is ...
Optional Parameters with C++ Macros
...rd trick to count the number of arguments to a macro.
enum
{
plain = 0,
bold = 1,
italic = 2
};
void PrintString(const char* message, int size, int style)
{
}
#define PRINT_STRING_1_ARGS(message) PrintString(message, 0, 0)
#define PRINT_STRING_2_ARGS(message, size) ...
How can I shrink the drawable on a button?
...rawable = getResources().getDrawable(R.drawable.s_vit);
drawable.setBounds(0, 0, (int)(drawable.getIntrinsicWidth()*0.5),
(int)(drawable.getIntrinsicHeight()*0.5));
ScaleDrawable sd = new ScaleDrawable(drawable, 0, scaleWidth, scaleHeight);
Button btn = findViewbyId(R.id.yo...
How to check if an int is a null
...
An int is not null, it may be 0 if not initialized.
If you want an integer to be able to be null, you need to use Integer instead of int.
Integer id;
String name;
public Integer getId() { return id; }
Besides the statement if(person.equals(null)) can...
How to configure PostgreSQL to accept all incoming connections
...
Just use 0.0.0.0/0.
host all all 0.0.0.0/0 md5
Make sure the listen_addresses in postgresql.conf (or ALTER SYSTEM SET) allows incoming connections on all available IP interfaces.
listen_addres...
Why is there no xrange function in Python3?
...pple 2.7.2 64-bit:
In [37]: %timeit collections.deque((x for x in xrange(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.05 s per loop
Now, python.org 3.3.0 64-bit:
In [83]: %timeit collections.deque((x for x in range(10000000) if x%4 == 0), maxlen=0)
1 loops, best of 3: 1.32 s per loop
...
What's the difference between “groups” and “captures” in .NET regular expressions?
...ew value. Not .NET, which will keep this history and places it in Captures[0].
If we change your regex to look as follows:
MatchCollection matches = Regex.Matches("{Q}{R}{S}", @"(\{[A-Z]\})+");
you will notice that the first Group will have one Captures (the first group always being the whole m...