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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...
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...
In c++ what does a tilde “~” before a function name signify?
...tc.
Here's a description from ibm.com:
Destructors are usually used to deallocate memory and do other cleanup for a class object and its class members when the object is destroyed. A destructor is called for a class object when that object passes out of scope or is explicitly deleted.
See https:/...
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...
What are five things you hate about your favorite language? [closed]
...
PHP:
1) Forces me to make unnecessary variables:
$parts = explode('|', $string);
$first = $parts[0];
2) An implementation of lambdas so lame it is roughly equivalent to using eval() and so hideously wrong I have never use...
proper way to sudo over ssh
...ssh -t user@server "sudo script"
See man ssh:
-t Force pseudo-tty allocation. This can be used to execute arbi-
trary screen-based programs on a remote machine, which can be
very useful, e.g., when implementing menu services. Multiple -t
options force tty alloca...
Preserve Line Breaks From TextArea When Writing To MySQL
...
Two solutions for this:
PHP function nl2br():
e.g.,
echo nl2br("This\r\nis\n\ra\nstring\r");
// will output
This<br />
is<br />
a<br />
string<br />
Wrap the input in <pre></pre> tags.
See: W3C Wiki - HTML/El...
What's the difference between deque and list STL containers?
...ime is linear if capacity is 10 and size is also 10. Its because it has to allocate and copy all the elements to new memory.
– aJ.
Apr 16 '10 at 3:25
5
...
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...
Objective-C class -> string like: [NSArray className] -> @“NSArray”
...
Class arrayClass = NSClassFromString (name);
id anInstance = [[arrayClass alloc] init];
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