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Change the name of a key in dictionary
...elete dictionary[old_key].
>>> dictionary = { 1: 'one', 2:'two', 3:'three' }
>>> dictionary['ONE'] = dictionary.pop(1)
>>> dictionary
{2: 'two', 3: 'three', 'ONE': 'one'}
>>> dictionary['ONE'] = dictionary.pop(1)
Traceback (most recent call last):
File "<inp...
Centering the pagination in bootstrap
...
Bootstrap has added a new class from 3.0.
<div class="text-center">
<ul class="pagination">
<li><a href="?p=0" data-original-title="" title="">1</a></li>
<li><a href="?p=1" data-original-title=""...
In c# is there a method to find the max of 3 numbers?
Like Math.Max but takes 3 or params of int?
10 Answers
10
...
Syntax for creating a two-dimensional array
...ti[0] = new int[10];
multi[1] = new int[10];
multi[2] = new int[10];
multi[3] = new int[10];
multi[4] = new int[10];
Note that every element will be initialized to the default value for int, 0, so the above are also equivalent to:
int[][] multi = new int[][]{
{ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
...
Ruby Bundle Symbol not found: _SSLv2_client_method (LoadError)
...y-2.1.2.tar.gz...
-> http://dqw8nmjcqpjn7.cloudfront.net/f22a6447811a81f3c808d1c2a5ce3b5f5f0955c68c9a749182feb425589e6635
Installing ruby-2.1.2...
Installed ruby-2.1.2 to /Users/ryan/.rbenv/versions/2.1.2
share
...
Obfuscated C Code Contest 2006. Please explain sykes2.c
...g:
main(_) {
_^448 && main(-~_);
putchar(--_%64
? 32 | -~7[__TIME__-_/8%8][">'txiZ^(~z?"-48] >> ";;;====~$::199"[_*2&8|_/64]/(_&2?1:8)%8&1
: 10);
}
Introducing variables to untangle this mess:
main(int i) {
if(i^448)
main(-~i);
...
How do I merge two dictionaries in a single expression in Python (taking union of dictionaries)?
...
6173
How can I merge two Python dictionaries in a single expression?
For dictionaries x and y, z be...
Is there a foreach in MATLAB? If so, how does it behave if the underlying data changes?
...in other languages. This means that the following code always prints 1, 2, 3, 4, 5 regardless of the value of B.
A = 1:5;
for i = A
A = B;
disp(i);
end
If you want to be able to respond to changes in the data structure during iterations, a WHILE loop may be more appropriate --- you'll be...
Callback functions in C++
...pe.
X.2 "Calling" a callback refers to the syntax to call those objects.
X.3 "Using" a callback means the syntax when passing arguments to a function using a callback.
Note: As of C++17, a call like f(...) can be written as std::invoke(f, ...) which also handles the pointer to member case.
1. Fun...
What is the most efficient way to create a dictionary of two pandas Dataframe columns?
...ies(df.Letter.values,index=df.Position).to_dict()
Out[9]: {1: 'a', 2: 'b', 3: 'c', 4: 'd', 5: 'e'}
Speed comparion (using Wouter's method)
In [6]: df = pd.DataFrame(randint(0,10,10000).reshape(5000,2),columns=list('AB'))
In [7]: %timeit dict(zip(df.A,df.B))
1000 loops, best of 3: 1.27 ms per loo...