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What are the differences between vector and list data types in R?
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As someone who's just gotten into R, but comes from a C/Java/Ruby/PHP/Python background, here's how I think of it.
A list is really an array + a hashmap. It's a PHP associative array.
> foo = list(bar='baz')
> foo[1]
'baz'
> foo$bar
'baz'
> foo[['bar']]
'baz'
A vector is a f...
Picking a random element from a set
...w array? docs.oracle.com/javase/7/docs/api/java/util/… "this method must allocate a new array even if this collection is backed by an array"
– anton1980
Nov 22 '14 at 3:19
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In STL maps, is it better to use map::insert than []?
...es") and are destroyed.
Which means extra time for:
1. One objects memory allocation
2. One extra constructor call
3. One extra destructor call
4. One objects memory deallocation
If your objects are large, constructors are typical, destructors do a lot of resource freeing, above points count even ...
File input 'accept' attribute - is it useful?
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If specified, the attribute must consist of a
set of comma-separated tokens,
each of which must be an
ASCII case-insensitive
match for one of the following:
The string audio/*
Indicates that sound files are accepted.
The string video/*
Indicates that video fi...
Why is try {…} finally {…} good; try {…} catch{} bad?
...atement. If you are only using a 'try' in order to ensure resources are de-allocated in the 'finally' block, you might consider the 'using' statement instead:
using (StreamReader reader = new StreamReader('myfile.txt'))
{
// do stuff here
} // reader.dispose() is called automatically
You can ...
Practical uses of different data structures [closed]
...tworks of communication, data organization etc.
Heap - Dynamic memory allocation in lisp
This is the answer originally posted by RV Pradeep
Some other, less useful links:
Applications are only listed for some data structures
Not application focused, by good summary and relevant
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How to quit android application programmatically
...nishAffinity(); without System.exit(0); your application will quit but the allocated memory will still be in use by your phone, so... if you want a clean and really quit of an app, use both of them.
This is the simplest method and works anywhere, quit the app for real, you can have a lot of activit...
REDHAT 6.4 X64下ORACLE 11GR2静默安装 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
...e is desired.
# If Automatic Memory Management is not desired, and memory allocation
# is to be done manually, then set it to false.
#11g的新特性自动内存管理，也就是SGA_TARGET和PAG_AGGREGATE_TARGET都不用设置了，Oracle会自动调配两部分大小。
#----------------------...
How do I prevent node.js from crashing? try-catch doesn't work
From my experience, a php server would throw an exception to the log or to the server end, but node.js just simply crashes. Surrounding my code with a try-catch doesn't work either since everything is done asynchronously. I would like to know what does everyone else do in their production servers.
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When do I need to use Begin / End Blocks and the Go keyword in SQL Server?
... the following lines. It doesn't "see" the symbol until it encounters a GO token which tells it to execute the preceding SQL since the last GO, at which point the symbol is applied to the database and becomes visible to the parser.
Why it doesn't just treat the semi-colon as a semantic break and ap...