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Deleting an element from an array in PHP
...t() which will convert all keys to numerical enumerated keys starting from 0.
Code
<?php
$array = [0 => "a", 1 => "b", 2 => "c"];
unset($array[1]);
//↑ Key which you want to delete
?>
Output
[
[0] => a
[2] => c
]
\array_splice() method
If yo...
Putting an if-elif-else statement on one line?
...st likely violate PEP-8 where it is mandated that lines should not exceed 80 characters in length.
It's also against the Zen of Python: "Readability counts". (Type import this at the Python prompt to read the whole thing).
You can use a ternary expression in Python, but only for expressions, not f...
What's the best way to send a signal to all members of a process group?
...
308
You don't say if the tree you want to kill is a single process group. (This is often the case ...
How to change navbar collapse threshold using Twitter bootstrap-responsive?
I'm using Twitter Bootstrap 2.0.1 in a Rails 3.1.2 project, implemented with bootstrap-sass. I'm loading both the bootstrap.css and the bootstrap-responsive.css files, as well as the bootstrap-collapse.js Javascript.
...
Why does (1 in [1,0] == True) evaluate to False?
...arison operator chaining here. The expression is translated to
(1 in [1, 0]) and ([1, 0] == True)
which is obviously False.
This also happens for expressions like
a < b < c
which translate to
(a < b) and (b < c)
(without evaluating b twice).
See the Python language documentat...
Convert columns to string in Pandas
...taFrame([['A', 2], ['A', 4], ['B', 6]])
In [12]: df.to_json()
Out[12]: '{"0":{"0":"A","1":"A","2":"B"},"1":{"0":2,"1":4,"2":6}}'
In [13]: df[0].to_json()
Out[13]: '{"0":"A","1":"A","2":"B"}'
Note: you can pass in a buffer/file to save this to, along with some other options...
...
iOS 7 TableView like in Settings App on iPad
...PathCreateMutable();
CGRect bounds = CGRectInset(cell.bounds, 10, 0);
BOOL addLine = NO;
if (indexPath.row == 0 && indexPath.row == [tableView numberOfRowsInSection:indexPath.section]-1) {
CGPathAddRoundedRect(pathRef, nil, bounds, cornerRa...
Finding duplicates in O(n) time and O(1) space
Input: Given an array of n elements which contains elements from 0 to n-1, with any of these numbers appearing any number of times.
...
Modify SVG fill color when being served as Background-Image
... |
edited Dec 21 '18 at 0:15
David Neto
72311 gold badge1111 silver badges2020 bronze badges
answered ...
Naming returned columns in Pandas aggregate function? [duplicate]
...
107
This will drop the outermost level from the hierarchical column index:
df = data.groupby(...)....