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MongoDB SELECT COUNT GROUP BY
...ier way to do it using aggregate:
db.contest.aggregate([
{"$group" : {_id:"$province", count:{$sum:1}}}
])
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Replacing spaces with underscores in JavaScript?
I'm trying to use this code to replace spaces with _, it works for the first space in the string but all the other instances of spaces remain unchanged. Anybody know why?
...
Random string generation with upper case letters and digits
...
Answer in one line:
''.join(random.choice(string.ascii_uppercase + string.digits) for _ in range(N))
or even shorter starting with Python 3.6 using random.choices():
''.join(random.choices(string.ascii_uppercase + string.digits, k=N))
A cryptographically more secure version...
iOS 7's blurred overlay effect using CSS?
...e want to try, so I did, check out the example here:
http://codepen.io/Edo_B/pen/cLbrt
Using:
HW Accelerated CSS filters
JS for class assigning and arrow key events
Images CSS Clip property
that's it.
I also believe this could be done dynamically for any screen if using canvas to copy the cu...
Iterate an iterator by chunks (of n) in Python? [duplicate]
...', 'x') --> ABC DEF Gxx"
args = [iter(iterable)] * n
return izip_longest(fillvalue=fillvalue, *args)
It will fill up the last chunk with a fill value, though.
A less general solution that only works on sequences but does handle the last chunk as desired is
[my_list[i:i + chunk_size] f...
What does the slash mean in help() output?
...meters could only be specified in the C API.
It means the key argument to __contains__ can only be passed in by position (range(5).__contains__(3)), not as a keyword argument (range(5).__contains__(key=3)), something you can do with positional arguments in pure-python functions.
Also see the Argum...
What it the significance of the Javascript constructor property?
...y to find attr among x's attributes. If it cant find it, it will look in x.__proto__. If it's not there either, it will look in x.__proto__.__proto__ and so on as long as __proto__ is defined.
So what is __proto__and what has it got to do with prototype? Shortly put, prototype is for "types" while ...
Comparing two NumPy arrays for equality, element-wise
... or simply want to be safe: use one of the specialized functions:
np.array_equal(A,B) # test if same shape, same elements values
np.array_equiv(A,B) # test if broadcastable shape, same elements values
np.allclose(A,B,...) # test if same shape, elements have close enough values
...
Best way to use PHP to encrypt and decrypt passwords? [duplicate]
... ' string to be encrypted '; // note the spaces
To Encrypt:
$iv = mcrypt_create_iv(
mcrypt_get_iv_size(MCRYPT_RIJNDAEL_128, MCRYPT_MODE_CBC),
MCRYPT_DEV_URANDOM
);
$encrypted = base64_encode(
$iv .
mcrypt_encrypt(
MCRYPT_RIJNDAEL_128,
hash('sha256', $key, true),
...
_DEBUG vs NDEBUG
...
Visual Studio defines _DEBUG when you specify the /MTd or /MDd option, NDEBUG disables standard-C assertions. Use them when appropriate, ie _DEBUG if you want your debugging code to be consistent with the MS CRT debugging techniques and NDEBUG if ...