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Element-wise addition of 2 lists?
...
371
Use map with operator.add:
>>> from operator import add
>>> list( map(add, ...
Most popular screen sizes/resolutions on Android phones [closed]
...king for.
– dfetter88
Jun 7 '11 at 23:07
21
That link says nothing of how common a resolution is....
How can I format a decimal to always show 2 decimal places?
...s Decimal('0.01')
>>> # Round to two places
>>> Decimal('3.214').quantize(TWOPLACES)
Decimal('3.21')
>>> # Validate that a number does not exceed two places
>>> Decimal('3.21').quantize(TWOPLACES, context=Context(traps=[Inexact]))
Decimal('3.21')
>>> Deci...
Evenly space multiple views within a container view
...at it worked.
Duh 2: The 'spacer views' could have been transparent.
Duh 3: This approach could be applied horizontally.
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PHP: merge two arrays while keeping keys instead of reindexing?
...
You can simply 'add' the arrays:
>> $a = array(1, 2, 3);
array (
0 => 1,
1 => 2,
2 => 3,
)
>> $b = array("a" => 1, "b" => 2, "c" => 3)
array (
'a' => 1,
'b' => 2,
'c' => 3,
)
>> $a + $b
array (
0 => 1,
1 => 2,
2 =&g...
How assignment works with Python list slice?
...ete, or replace contents from a list:
Insertion:
>>> a = [1, 2, 3]
>>> a[0:0] = [-3, -2, -1, 0]
>>> a
[-3, -2, -1, 0, 1, 2, 3]
Deletion:
>>> a
[-3, -2, -1, 0, 1, 2, 3]
>>> a[2:4] = []
>>> a
[-3, -2, 1, 2, 3]
Replacement:
>>> a
[-...
No secret option provided to Rack::Session::Cookie warning?
I am running Rails 3.2.3, Ruby 1.9 under Fedora 17. I get this warning, when I run rails s , and how do I fix?
7 Answers
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How to use background thread in swift?
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Swift 3.0+
A lot has been modernized in Swift 3.0. Running something on the background thread looks like this:
DispatchQueue.global(qos: .background).async {
print("This is run on the background queue")
DispatchQueue.mai...
while (1) vs. while(True) — Why is there a difference (in python 2 bytecode)?
...
3 Answers
3
Active
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How to iterate a loop with index and element in Swift
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Yes. As of Swift 3.0, if you need the index for each element along with its value, you can use the enumerated() method to iterate over the array. It returns a sequence of pairs composed of the index and the value for each item in the array. F...