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Python - Create a list with initial capacity
...
def doAppend( size=10000 ):
result = []
for i in range(size):
message= "some unique object %d" % ( i, )
result.append(message)
return result
def doAllocate( size=10000 ):
result=size*[None]
for i in range(size):
message= "some unique obj...
Python Sets vs Lists
...(iterable)",
... setup="from __main__ import iter_test; iterable = set(range(10000))",
... number=100000)
12.666952133178711
>>> timeit(
... "iter_test(iterable)",
... setup="from __main__ import iter_test; iterable = list(range(10000))",
... number=100000)
9.91709899902...
Iterating C++ vector from the end to the beginning
...
The well-established "pattern" for reverse-iterating through closed-open ranges looks as follows
// Iterate over [begin, end) range in reverse
for (iterator = end; iterator-- != begin; ) {
// Process `*iterator`
}
or, if you prefer,
// Iterate over [begin, end) range in reverse
for (iterato...
“for loop” with two variables? [duplicate]
...of a nested for loop, use:
import itertools
for i, j in itertools.product(range(x), range(y)):
# Stuff...
If you just want to loop simultaneously, use:
for i, j in zip(range(x), range(y)):
# Stuff...
Note that if x and y are not the same length, zip will truncate to the shortest list. ...
Sort Go map values by keys
... in action has an excellent explanation.
When iterating over a map with a range loop, the iteration order is
not specified and is not guaranteed to be the same from one iteration
to the next. Since Go 1 the runtime randomizes map iteration order, as
programmers relied on the stable iteration order ...
Why is it slower to iterate over a small string than a small list?
...building of the list, but it's still faster for this. Python 2 is acting strangely fast.
Let's remove the comprehensions and re-time. The _ = is to prevent it getting optimised out.
>>> python3 -m timeit '_ = ["a", "b", "c"]'
10000000 loops, best of 3: 0.0707 usec per loop
>>> p...
How to calculate the difference between two dates using PHP?
.... I still believe that for most purposes that's fine, since the usage of a range is more to provide a sense of how much time has passed or remains rather than to provide precision - if you want to do that, just output the date.
Despite all that, I've decided to address the complaints. If you truly...
How to create the most compact mapping n → isprime(n) up to a limit N?
...ithm that produces a data structure with lowest memory consumption for the range (1, N], where N is a constant.
Just an example of what I am looking for: I could represent every odd number with one bit e.g. for the given range of numbers (1, 10], starts at 3: 1110
...
Alphabet range in Python
...'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z']
And to do it with range
>>> list(map(chr, range(97, 123))) #or list(map(chr, range(ord('a'), ord('z')+1)))
['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', ...
Max length UITextField
...otocol:
func textField(_ textField: UITextField, shouldChangeCharactersIn range: NSRange, replacementString string: String) -> Bool {
guard let textFieldText = textField.text,
let rangeOfTextToReplace = Range(range, in: textFieldText) else {
return false
}
let sub...