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When should I use @classmethod and when def method(self)?
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Your guess is correct - you understand how classmethods work.
The why is that these methods can be called both on an instance OR on the class (in both cases, the class object will be passed as the first argument):
class Dummy(object):
@classmethod
d...
How can I remove a character from a string using Javascript?
...ing.replace(/\/r/g, '/');
EDIT:
Since everyone's having so much fun here and user1293504 doesn't seem to be coming back any time soon to answer clarifying questions, here's a method to remove the Nth character from a string:
String.prototype.removeCharAt = function (i) {
var tmp = this.split(...
Regex for splitting a string using space when not surrounded by single or double quotes
I'm new to regular expressions and would appreciate your help. I'm trying to put together an expression that will split the example string using all spaces that are not surrounded by single or double quotes. My last attempt looks like this: (?!") and isn't quite working. It's splitting on the spa...
pandas: multiple conditions while indexing data frame - unexpected behavior
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As you can see, the AND operator drops every row in which at least one
value equals -1. On the other hand, the OR operator requires both
values to be equal to -1 to drop them.
That's right. Remember that you're writing the condition in te...
Test whether a glob has any matches in bash
...compgen -G "<glob-pattern>"
Escape the pattern or it'll get pre-expanded into matches.
Exit status is:
1 for no-match,
0 for 'one or more matches'
stdout is a list of files matching the glob.
I think this is the best option in terms of conciseness and minimizing potential side effect...
What does the “yield” keyword do?
What is the use of the yield keyword in Python, and what does it do?
42 Answers
42
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How can I sort arrays and data in PHP?
... sorts low-to-high or reverse ("r"), whether it sorts values or keys ("k") and how it compares values ("nat" vs. normal). See http://php.net/manual/en/array.sorting.php for an overview and links to further details.
Multi dimensional arrays, including arrays of objects
$array = array(
array('foo'...
IN vs OR in the SQL WHERE Clause
...rding to the manual for MySQL if the values are constant IN sorts the list and then uses a binary search. I would imagine that OR evaluates them one by one in no particular order. So IN is faster in some circumstances.
The best way to know is to profile both on your database with your specific dat...
How to overload functions in javascript?
...ariable arguments - You can pass different sets of arguments (in both type and quantity) and the function will behave in a way that matches the arguments passed to it.
Default arguments - You can define a default value for an argument if it is not passed.
Named arguments - Argument order becomes irr...
Can someone give an example of cosine similarity, in a very simple, graphical way?
... want to know how similar these texts are, purely in terms of word counts (and ignoring word order). We begin by making a list of the words from both texts:
me Julie loves Linda than more likes Jane
Now we count the number of times each of these words appears in each text:
me 2 2
Jane ...