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How to use a decimal range() step value?

... @LarsWirzenius: in Python 2.2+, from __future__ import division; 3/10 returns 0.3. This behaviour is the default in Python 3.x. – Benjamin Hodgson♦ Sep 14 '12 at 11:15 ...
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How to run code when a class is subclassed? [duplicate]

...on2 you would define the metaclass of a class with class SuperClass: __metaclass__ = Watcher where Watcher is a subclass of type. In Python3 the syntax has been changed to class SuperClass(metaclass=Watcher) Both are equivalent to Superclass = Watcher(name, bases, clsdict) where in t...
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How to print the contents of RDD?

.... // For implicit conversion from RDD to DataFrame import spark.implicits._ fruits = sc.parallelize([("apple", 1), ("banana", 2), ("orange", 17)]) // convert to DF then show it fruits.toDF().show() This will show the top 20 lines of your data, so the size of your data should not be an issue. +...
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Execute code when Django starts ONCE only?

...d executed once. urls.py from django.confs.urls.defaults import * from my_app import one_time_startup urlpatterns = ... one_time_startup() share | improve this answer | ...
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MongoDB Aggregation: How to get total records count?

...te(array( array('$match' => $document), array('$group' => array('_id' => '$book_id', 'date' => array('$max' => '$book_viewed'), 'views' => array('$sum' => 1))), array('$sort' => $sort), // get total, AND preserve the results array('$group' => array('_id' => nu...
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How to manually expand a special variable (ex: ~ tilde) in bash

... +1 -- I was needing to expand ~$some_other_user and eval works fine when $HOME will not work because I don't need the current user home. – olivecoder Sep 10 '13 at 11:30 ...
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serve current directory from command line

...t that it serves everything. ruby -rsocket -e 's=TCPServer.new(5**5);loop{_=s.accept;_<<"HTTP/1.0 200 OK\r\n\r\n#{File.read(_.gets.split[1])rescue nil}";_.close}' I found it here Chris share | ...
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Best way to format integer as string with leading zeros? [duplicate]

... dynamically create the formatting string, [('{{0:0{0:d}d}}').format(len(my_list)).format(k) for k in my_list] – Mark Aug 28 '15 at 8:31 ...
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What is the Java string pool and how is “s” different from new String(“s”)? [duplicate]

... a reference to an instance of class String, and is derived from a CONSTANT_String_info structure (§4.4.3) in the binary representation of a class or interface. The CONSTANT_String_info structure gives the sequence of Unicode code points constituting the string literal. The Java programming la...
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Super-simple example of C# observer/observable with delegates

...Here's a simple example: public class ObservableClass { private Int32 _Value; public Int32 Value { get { return _Value; } set { if (_Value != value) { _Value = value; OnValueChanged(); } ...