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Can I use Objective-C blocks as properties?
... I didn't know that, thanks! ... Although I often do @synthesize myProp = _myProp
– Robert
Nov 8 '12 at 8:04
...
Principal component analysis in Python
...is 2 x 20. Dropping the primes,
d . Vt 2 principal vars = p.vars_pc( 20 vars )
U 1000 obs = p.pc_obs( 2 principal vars )
U . d . Vt 1000 obs, p.obs( 20 vars ) = pc_obs( vars_pc( vars ))
fast approximate A . vars, using the `npc` principal components
Ut ...
Hidden Features of PHP? [closed]
...
I agree. Being able to type www.php.net/function_name and getting a reference most of the time is great.
– Allain Lalonde
Sep 14 '08 at 17:46
1
...
Multiple Models in a single django ModelForm?
...
But how? Usually a FormView only has a single form_class assigned to it.
– erikbwork
Oct 7 '16 at 17:42
...
Sql Server string to date conversion
...r.
– Philip Kelley
Jan 23 '13 at 15:06
24
@PhilipKelley I don't see where the OP wants to know ho...
Detect & Record Audio in Python
...
from struct import pack
import pyaudio
import wave
THRESHOLD = 500
CHUNK_SIZE = 1024
FORMAT = pyaudio.paInt16
RATE = 44100
def is_silent(snd_data):
"Returns 'True' if below the 'silent' threshold"
return max(snd_data) < THRESHOLD
def normalize(snd_data):
"Average the volume out"
...
Use of #pragma in C
... == 7
Here's how you'd do the same thing in GCC:
struct PackedStructure __attribute__((__packed__))
{
char a;
int b;
short c;
};
// sizeof(PackedStructure == 7)
The GCC code is more portable, because if you want to compile that with a non-GCC compiler, all you have to do is
#define __att...
Are list-comprehensions and functional functions faster than “for loops”?
...(<the code object for `[x for x in range(10)]`>)
1 0 BUILD_LIST 0
3 LOAD_FAST 0 (.0)
>> 6 FOR_ITER 12 (to 21)
9 STORE_FAST 1 (x)
12 LOAD_FAST 1 (x)
...
Connection timeout for SQL server
...ng called.
– 3Dave
Nov 29 '10 at 22:06
Not according to this msdn blog post: blogs.msdn.com/b/spike/archive/2008/07/31...
Pragma in define macro
...
If you're using c99 or c++0x there is the pragma operator, used as
_Pragma("argument")
which is equivalent to
#pragma argument
except it can be used in macros (see section 6.10.9 of the c99 standard, or 16.9 of the c++0x final committee draft)
For example,
#define STRINGIFY(a) #a
#def...