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Change values while iterating
...o, the abbreviation you want is not possible.
The reason for this is that range copies the values from the slice you're iterating over.
The specification about range says:
Range expression 1st value 2nd value (if 2nd variable is present)
array or slice a [n...
Random string generation with upper case letters and digits
...e:
''.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; see https://stackoverflow.com/a/237...
Way to get all alphabetic chars in an array in PHP?
...
$alphas = range('A', 'Z');
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Using switch statement with a range of value in each case?
... works great and is simple. Also if you want to select numbers not in the range all you need is if(!isBetween... , good job.
– a54studio
Jul 20 '13 at 13:43
1
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How to get all subsets of a set? (powerset)
... list(iterable)
return chain.from_iterable(combinations(s, r) for r in range(len(s)+1))
Output:
>>> list(powerset("abcd"))
[(), ('a',), ('b',), ('c',), ('d',), ('a', 'b'), ('a', 'c'), ('a', 'd'), ('b', 'c'), ('b', 'd'), ('c', 'd'), ('a', 'b', 'c'), ('a', 'b', 'd'), ('a', 'c', 'd'), (...
Index all *except* one item in python
...st comp. For example, to make b a copy of a without the 3rd element:
a = range(10)[::-1] # [9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
b = [x for i,x in enumerate(a) if i!=3] # [9, 8, 7, 5, 4, 3, 2, 1, 0]
This is very general, and can be used with all iterables, including numpy arrays...
Generate random numbers uniformly over an entire range
...perator. That method may not generate numbers uniformly (it depends on the range and the value of RAND_MAX), and is therefore discouraged.
C++11 and generation over a range
With C++11 multiple other options have risen. One of which fits your requirements, for generating a random number in a range, p...
How to limit the maximum value of a numeric field in a Django model?
...is there any way to restrict it to storing only numbers within a certain range, e.g. 0.0-5.0 ?
6 Answers
...
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(...
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...