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C++ Dynamic Shared Library on Linux
...
myclass.h
#ifndef __MYCLASS_H__
#define __MYCLASS_H__
class MyClass
{
public:
MyClass();
/* use virtual otherwise linker will try to perform static linkage */
virtual void DoSomething();
private:
int x;
};
#endif
myclass.cc
#inc...
How can I generate a unique ID in Python? [duplicate]
...have to manually kill uuidd as root. I worked around this by setting uuid._uuid_generate_time and uuid._uuid_generate_random to None so the uuid module never used the native implementation. (That should really be an option anyway; generating V4 random UUIDs causing a daemon to be started is comple...
UIActionSheet cancel button strange behaviour
...ted unless I try to click on the "Cancel" button. The target of the button appears to have moved up from where it should be. I can only activate it by clicking somewhere in the middle of the "Cancel" and "Ok" buttons.
...
Are Stored Procedures more efficient, in general, than inline statements on modern RDBMS's? [duplica
...MySQL, and SQL Server DBA on-and off since for almost a decade (along with application development in C, PHP, PL/SQL, C#.NET, and Ruby). So, I have no particular axe to grind in this (sometimes) holy war.
The historical performance benefit of stored procs have generally been from the following (in...
What's the difference between compiled and interpreted language?
...e, as is done in Lua, Python, Ruby, Smalltalk, and many other systems (the approach was popularized in the 1970s by the UCSD P-system and UCSD Pascal)
A tree-like representation of the original program, such as an abstract-syntax tree, as is done for many prototype or educational interpreters
A toke...
How to convert Strings to and from UTF8 byte arrays in Java
...]:
String s = "some text here";
byte[] b = s.getBytes(StandardCharsets.UTF_8);
Convert from byte[] to String:
byte[] b = {(byte) 99, (byte)97, (byte)116};
String s = new String(b, StandardCharsets.US_ASCII);
You should, of course, use the correct encoding name. My examples used US-ASCII and UT...
Plot two histograms on single chart with matplotlib
...dom
import numpy
from matplotlib import pyplot
x = [random.gauss(3,1) for _ in range(400)]
y = [random.gauss(4,2) for _ in range(400)]
bins = numpy.linspace(-10, 10, 100)
pyplot.hist(x, bins, alpha=0.5, label='x')
pyplot.hist(y, bins, alpha=0.5, label='y')
pyplot.legend(loc='upper right')
pyplot....
Memoization in Haskell?
...alling, for example: fix f 123 = 144
We could memoize this by defining:
f_list :: [Int]
f_list = map (f faster_f) [0..]
faster_f :: Int -> Int
faster_f n = f_list !! n
That performs passably well, and replaces what was going to take O(n^3) time with something that memoizes the intermediate r...
Convert Python dictionary to JSON array
...
If you are fine with non-printable symbols in your json, then add ensure_ascii=False to dumps call.
>>> json.dumps(your_data, ensure_ascii=False)
If ensure_ascii is false, then the return value will be a
unicode instance subject to normal Python str to unicode
coercion rules in...
sizeof single struct member in C
...ic way to do it, another would be to use a macro like this:
#define member_size(type, member) sizeof(((type *)0)->member)
and use it like this:
typedef struct
{
float calc;
char text[255];
int used;
} Parent;
typedef struct
{
char flag;
char text[member_size(Parent, text)...