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Index all *except* one item in python
... 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. If you replace [] with (), b will be an iterator inst...
Searching for UUIDs in text with regex
...y I'm relying on the assumption that all UUIDs will follow a patttern of 8-4-4-4-12 hexadecimal digits.
16 Answers
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Why is [1,2] + [3,4] = “1,23,4” in JavaScript?
...t how the + operator behaves in general also.
So, here it goes.
Excluding E4X and implementation-specific stuff, Javascript (as of ES5) has 6 built-in data types:
Undefined
Null
Boolean
Number
String
Object
Note that although typeof somewhat confusingly returns object for Null and function for cal...
How to delete an element from an array in C#
...
342
If you want to remove all instances of 4 without needing to know the index:
LINQ: (.NET Framew...
How do you rotate a two dimensional array?
Inspired by Raymond Chen's post , say you have a 4x4 two dimensional array, write a function that rotates it 90 degrees. Raymond links to a solution in pseudo code, but I'd like to see some real world stuff.
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Select first 4 rows of a data.frame in R
How can I select the first 4 rows of a data.frame :
5 Answers
5
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Understanding slice notation
...
4772
It's pretty simple really:
a[start:stop] # items start through stop-1
a[start:] # item...
Get Android API level of phone currently running my application [duplicate]
...
4 Answers
4
Active
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Using numpy to build an array of all combinations of two arrays
...implementation:
@pv's solution
In [113]:
%timeit cartesian(([1, 2, 3], [4, 5], [6, 7]))
10000 loops, best of 3: 135 µs per loop
In [114]:
cartesian(([1, 2, 3], [4, 5], [6, 7]))
Out[114]:
array([[1, 4, 6],
[1, 4, 7],
[1, 5, 6],
[1, 5, 7],
[2, 4, 6],
[2, 4, 7],...
In a bootstrap responsive page how to center a div
...
UPDATE for Bootstrap 4
Simpler vertical grid alignement with flex-box
@import url('https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-alpha.6/css/bootstrap.min.css');
html,
body {
height: 100%
}
<div class="h-100 row align-items-cent...
