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List comprehension: Returning two (or more) items for each item
...mbda x: x ** 2
>>> list(chain.from_iterable((f(x), g(x)) for x in range(3)))
[2, 0, 3, 1, 4, 4]
Timings:
from timeit import timeit
f = lambda x: x + 2
g = lambda x: x ** 2
def fg(x):
yield f(x)
yield g(x)
print timeit(stmt='list(chain.from_iterable((f(x), g(x)) for x in range(...
Range references instead values
I saw that range returns the key and the "copy" of the value. Is there a way for that range to return the adress of the item? Example
...
Numpy first occurrence of value greater than existing value
...ned.") and doesn't save another list.
In [2]: N = 10000
In [3]: aa = np.arange(-N,N)
In [4]: timeit np.argmax(aa>N/2)
100000 loops, best of 3: 52.3 us per loop
In [5]: timeit np.where(aa>N/2)[0][0]
10000 loops, best of 3: 141 us per loop
In [6]: timeit np.nonzero(aa>N/2)[0][0]
10000 lo...
Create array of all integers between two numbers, inclusive, in Javascript/jQuery [duplicate]
...
In JavaScript ES6:
function range(start, end) {
return Array(end - start + 1).fill().map((_, idx) => start + idx)
}
var result = range(9, 18); // [9, 10, 11, 12, 13, 14, 15, 16, 17, 18]
console.log(result);
For completeness, here it is w...
HTML5: Slider with two inputs possible?
...o make a HTML5 slider with two input values, for example to select a price range? If so, how can it be done?
5 Answers
...
Fastest way to determine if an integer is between two integers (inclusive) with known sets of values
...operator.
if ((unsigned)(number-lower) <= (upper-lower))
in_range(number);
With a typical, modern computer (i.e., anything using twos complement), the conversion to unsigned is really a nop -- just a change in how the same bits are viewed.
Note that in a typical case, you can pre-c...
“is” operator behaves unexpectedly with integers
...ts for all
integers between -5 and 256, when you
create an int in that range you
actually just get back a reference to
the existing object. So it should be
possible to change the value of 1. I
suspect the behaviour of Python in
this case is undefined. :-)
...
How do I get a Cron like scheduler in Python? [closed]
... = CronTab(
Event(perform_backup, 0, 2, dow=6 ),
Event(purge_temps, 0, range(9,18,2), dow=range(0,5))
)
This way you get the full power of Python's argument mechanics (mixing positional and keyword args, and can use symbolic names for names of weeks and months)
The CronTab class would be defi...
What's the best way to iterate over two or more containers simultaneously
...erate over indices. But not with the classical for loop but instead with a range-based for loop over the indices:
for(unsigned i : indices(containerA)) {
containerA[i] = containerB[i];
}
indices is a simple wrapper function which returns a (lazily evaluated) range for the indices. Since the i...
What is the most accurate way to retrieve a user's correct IP address in PHP?
... if (filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_NO_PRIV_RANGE | FILTER_FLAG_NO_RES_RANGE) !== false){
return $ip;
}
}
}
}
}
Your code seems to be pretty complete already, I cannot see any possible bugs in it (aside from...