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How can i get the session object if i have the entity-manager
...otally exhaustive, things are different if you're using a JPA 1.0 or a JPA 2.0 implementation.
JPA 1.0
With JPA 1.0, you'd have to use EntityManager#getDelegate(). But keep in mind that the result of this method is implementation specific i.e. non portable from application server using Hibernate ...
Create objective-c class instance by name?
...utilize the Objective-C language runtime library's API. Under Objective-C 2.0:
#import <objc/runtime.h>
//Declaration in the above named file
id objc_getClass(const char* name);
//Usage
id c = objc_getClass("Object");
[ [ c alloc ] free ];
Under the Objective-C (1.0 or unnamed version) you...
Android Center text on canvas
...t() - mPaint.ascent();
bounds.left += (r.width() - bounds.right) / 2.0f;
bounds.top += (r.height() - bounds.bottom) / 2.0f;
yourCanvas.drawText(pageTitle, bounds.left, bounds.top - mPaint.ascent(), mPaint);
}
@Override
protected void onSizeChanged(int w, int h, i...
Multiprocessing: How to use Pool.map on a function defined in a class?
...or p in proc]
return [p.recv() for (p, c) in pipe]
if __name__ == '__main__':
print parmap(lambda x: x**x, range(1, 5))
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Defeating a Poker Bot
...
classify rogue cheating or robotic
players.
Back when online poker was a fairly
new entity, there was rumour and talk with limited evidence that
some poker client software
screen-shots of suspicious players
desktops to see if they were running
programs that assist them. However (even if this were ...
What is the difference between float and double?
... + 3.9999999 = 0, the exact roots to 10 significant digits are, r1 = 2.000316228 and r2 = 1.999683772.
Using float and double, we can write a test program:
#include <stdio.h>
#include <math.h>
void dbl_solve(double a, double b, double c)
{
double d = b*b - 4.0*a*c;
dou...
What algorithms compute directions from point A to point B on a map?
...tion, you can have several layers of map data: A 'highways' layer that contains only highways, a 'secondary' layer that contains only secondary streets, and so forth. Then, you explore only smaller sections of the more detailed layers, expanding as necessary. Obviously this description leaves out a ...
What is the C++ function to raise a number to a power?
...yped so it matches one of those three perfectly. I usually use double
pow(2.0, N)
Some lawyer crap from me again. I've often fallen in this pitfall myself, so I'm going to warn you about it.
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Log to the base 2 in python
...
float → float math.log2(x)
import math
log2 = math.log(x, 2.0)
log2 = math.log2(x) # python 3.4 or later
Thanks @akashchandrakar and @unutbu.
float → int math.frexp(x)
If all you need is the integer part of log base 2 of a floating point number, extracting the exponent i...
When to encode space to plus (+) or %20?
...www-form-urlencoded'. This is used for posting form data.
Now, the HTML 2.0 Specification (RFC1866) explicitly said, in section 8.2.2, that the Query part of a GET request's URL string should be encoded as 'application/x-www-form-urlencoded'. This, in theory, suggests that it's legal to use a '...