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Python: List vs Dict for look up table
... sets, running python 2.7.3 on an i7 CPU on linux:
python -mtimeit -s 'd=range(10**7)' '5*10**6 in d'
10 loops, best of 3: 64.2 msec per loop
python -mtimeit -s 'd=dict.fromkeys(range(10**7))' '5*10**6 in d'
10000000 loops, best of 3: 0.0759 usec per loop
python -mtimeit -s 'from sets import Set...
Difference between signed / unsigned char [duplicate]
...E2;
BYTE1 a;
BYTE2 b;
For variable a, only 7 bits are available and its range is (-127 to 127) = (+/-)2^7 -1.
For variable b all 8 bits are available and the range is 0 to 255 (2^8 -1).
If you use char as character, "unsigned" is completely ignored by the compiler just as comments are removed f...
How to use UTF-8 in resource properties with ResourceBundle
...d to save them as ISO-8859-1. If you have any characters beyond ISO-8859-1 range and you can't use \uXXXX off top of head and you're thus forced to save the file as UTF-8, then you'd need to use the native2ascii tool to convert an UTF-8 saved properties file to an ISO-8859-1 saved properties file wh...
How to display request headers with command line curl
... 11-Feb-2017 15:45:36 GMT; path=/; domain=.google.de; HttpOnly
< Accept-Ranges: none
< Vary: Accept-Encoding
< Transfer-Encoding: chunked
<
{ [11080 bytes data]
* Connection #1 to host www.google.de left intact
As you can see curl outputs both the outgoing and the incoming headers and ...
How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
...es and use that to index into your frame:
>>> df = pd.DataFrame([range(3), [0, np.NaN, 0], [0, 0, np.NaN], range(3), range(3)])
>>> df.isnull()
0 1 2
0 False False False
1 False True False
2 False False True
3 False False False
4 False False False...
How to step through Python code to help debug issues?
... __init__(self):
self.count= 9
def go(self):
for i in range(self.count):
pdb.set_trace()
print i
return
if __name__ == '__main__':
MyObj(5).go()
Step-by-Step debugging to go into more internal
Execute the next statement… with “n” (n...
Multiple variables in a 'with' statement?
... print('exit {!r}'.format(self))
return True
xs = [X() for _ in range(3)]
with ExitStack() as stack:
print(stack._exit_callbacks)
nums = [stack.enter_context(x) for x in xs]
print(stack._exit_callbacks)
print(stack._exit_callbacks)
print(nums)
Output:
deque([])
enter X1
en...
Python Unicode Encode Error
...ascii' codec can't encode character '\ua000' in position 0: ordinal not in range(128)
>>> u.encode('ascii', 'ignore')
'abcd'
>>> u.encode('ascii', 'replace')
'?abcd?'
>>> u.encode('ascii', 'xmlcharrefreplace')
'&#40960;abcd&#1972;'
You might want to read this art...
What's the “average” requests per second for a production web application?
...r your question, we have been doing a huge load test ourselves and find it ranges on various amazon hardware we use(best value was the 32 bit medium cpu when it came down to $$ / event / second) and our requests / seconds ranged from 29 requests / second / node up to 150 requests/second/node.
Giving...
How to retrieve all keys (or values) from a std::map and put them into a vector?
...
There is a boost range adaptor for this purpose:
#include <boost/range/adaptor/map.hpp>
#include <boost/range/algorithm/copy.hpp>
vector<int> keys;
boost::copy(m | boost::adaptors::map_keys, std::back_inserter(keys));
There...