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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 to split a delimited string in Ruby and convert it to an array?
...
>> "1,2,3,4".split(",")
=> ["1", "2", "3", "4"]
Or for integers:
>> "1,2,3,4".split(",").map { |s| s.to_i }
=> [1, 2, 3, 4]
Or for later versions of ruby (>= 1.9 - as pointed out by Alex):
>> "1,2,3,4".spli...
Change the color of glyphicons to blue in some- but not at all places using Bootstrap 2
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answered Aug 20 '13 at 12:32
Vikas GhodkeVikas Ghodke
6,29855 gold badges2323 silver badges3737 bronze badges
...
std::next_permutation Implementation Explanation
...
Let's look at some permutations:
1 2 3 4
1 2 4 3
1 3 2 4
1 3 4 2
1 4 2 3
1 4 3 2
2 1 3 4
...
How do we go from one permutation to the next? Firstly, let's look at things a little differently. We can view the elements as digits and the permutations as numbers. ...
Determining complexity for recursive functions (Big O notation)
...
362
The time complexity, in Big O notation, for each function:
int recursiveFun1(int n)
{
if ...
Split comma-separated strings in a column into separate rows
...th more than about 5000 rows, Jaap's data.table method 2 and the variant DT3 are the fastest, magnitudes faster than the slowest methods.
Remarkably, the timings of the two tidyverse methods and the splistackshape solution are so similar that it's difficult to distiguish the curves in the chart. T...
Select count(*) from multiple tables
...
337
SELECT (
SELECT COUNT(*)
FROM tab1
) AS count1,
(
S...
Pandas dataframe get first row of each group
...;> df.groupby('id').first()
value
id
1 first
2 first
3 first
4 second
5 first
6 first
7 fourth
If you need id as column:
>>> df.groupby('id').first().reset_index()
id value
0 1 first
1 2 first
2 3 first
3 4 second
4 5 first
5 6...
List comprehension: Returning two (or more) items for each item
...: 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(3)))',...
List of lists into numpy array
...answer of Ignacio Vazquez-Abrams will not work. Instead there are at least 3 options:
1) Make an array of arrays:
x=[[1,2],[1,2,3],[1]]
y=numpy.array([numpy.array(xi) for xi in x])
type(y)
>>><type 'numpy.ndarray'>
type(y[0])
>>><type 'numpy.ndarray'>
2) Make an arr...