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Forward an invocation of a variadic function in C
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If you don't have a function analogous to vfprintf that takes a va_list instead of a variable number of arguments, you can't do it. See http://c-faq.com/varargs/handoff.html.
Example:
void myfun(const char *fmt, va_list argp) {
vfprintf(stderr, fmt, argp);
}
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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
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Access multiple elements of list knowing their index
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Alternatives:
>>> map(a.__getitem__, b)
[1, 5, 5]
>>> import operator
>>> operator.itemgetter(*b)(a)
(1, 5, 5)
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impro...
Multiple Models in a single django ModelForm?
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But how? Usually a FormView only has a single form_class assigned to it.
– erikbwork
Oct 7 '16 at 17:42
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Detect & Record Audio in Python
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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"
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Timeout for python requests.get entire response
...snippet will work for you:
import requests
import eventlet
eventlet.monkey_patch()
with eventlet.Timeout(10):
requests.get("http://ipv4.download.thinkbroadband.com/1GB.zip", verify=False)
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Pragma in define macro
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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...
Open link in new tab or window [duplicate]
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You should add the target="_blank" and rel="noopener noreferrer" in the anchor tag.
For example:
<a target="_blank" rel="noopener noreferrer" href="http://your_url_here.html">Link</a>
Adding rel="noopener noreferrer" is not mandatory, b...
Operation on every pair of element in a list
...,1 3,2 3,3 3,4
4,1 4,2 4,3 4,4
permutations() generates all unique orderings of each unique pair of elements, eliminating the x,x duplicates:
. 1,2 1,3 1,4
2,1 . 2,3 2,4
3,1 3,2 . 3,4
4,1 4,2 4,3 .
Finally, combinations() only generates each unique pair of elements, in ...
Why is it slower to iterate over a small string than a small list?
...sions. I'll examine the compiled code.
For Python 3:
import dis
def list_iterate():
[item for item in ["a", "b", "c"]]
dis.dis(list_iterate)
#>>> 4 0 LOAD_CONST 1 (<code object <listcomp> at 0x7f4d06b118a0, file "", line 4>)
#>>> ...