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How to delete a row by reference in data.table?
...nce yet.
data.table can add and delete columns by reference since it over-allocates the vector of column pointers, as you know. The plan is to do something similar for rows and allow fast insert and delete. A row delete would use memmove in C to budge up the items (in each and every column) after t...
String's Maximum length in Java - calling length() method
...ver, there probably are going to be other limitations, such as the maximum allocatable size for an array.
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Generating Guids in Ruby
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How to create small, unique tokens in Ruby
>> require 'digest'
=> []
>> Digest::SHA1.hexdigest("some-random-string")[8..16]
=> "2ebe5597f"
>> SecureRandom.base64(8).gsub("/","_").gsub(/=+$/,"")
=> "AEWQyovNFo0"
>> ra...
Does the C++ standard mandate poor performance for iostreams, or am I just dealing with a poor imple
...sing work. In your char[] array example, the array of the required size is allocated in advance. In your vector and ostringstream example you are forcing the objects to repeatedly allocate and reallocate and possibly copy data many times as the object grows.
With std::vector this is easly resolved...
How to unit test an object with database queries
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I've been using PHP's PDO as my lowest level access to the database, over which I extracted an interface. Then I built an application aware database layer on top of that. This is the layer that holds all the raw SQL queries and other infor...
Using a BOOL property
...fit to using properties with primitive types. @property is used with heap allocated NSObjects like NSString*, NSNumber*, UIButton*, and etc, because memory managed accessors are created for free. When you create a BOOL, the value is always allocated on the stack and does not require any special ac...
Why is  appearing in my HTML? [duplicate]
...
Try:
<?php
// Tell me the root folder path.
// You can also try this one
// $HOME = $_SERVER["DOCUMENT_ROOT"];
// Or this
// dirname(__FILE__)
$HOME = dirname(__FILE__);
// Is this a Windows host ? If it is, change this line to $W...
Java8 Lambdas vs Anonymous classes
...st don't try to use your counter from multiple threads. If you're going to allocate something on the heap and capture it in a lambda, you might as well use an AIC and add a field that you can mutate directly. Using a lambda this way can work, but why bother when you can use a real object?
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OOP vs Functional Programming vs Procedural [closed]
..., but I really can't see the big difference between it and procedural C or PHP, could you give some example?
– Leonel
Apr 1 '12 at 2:39
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How can I use a carriage return in a HTML tooltip?
... @Tarquin They don't work in HTML, they just work specifically in PHP's double quotes because that's a feature of PHP's double quotes.
– Brilliand
May 26 '15 at 19:11
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