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Calling Objective-C method from C++ member function?
...hat C++ class a objective-C function [context renderbufferStorage:GL_RENDERBUFFER fromDrawable:(CAEAGLLayer*)self.layer]; which I cannot do in C++ syntax.
...
How do I perform the SQL Join equivalent in MongoDB?
...ttps://docs.mongodb.org/master/reference/operator/aggregation/lookup/#pipe._S_lookup
From the docs:
{
$lookup:
{
from: <collection to join>,
localField: <field from the input documents>,
foreignField: <field from the documents of the "from" collection>...
Getting the name of a child class in the parent class (static context)
...ot possible. in php4 you could implement a terrible hack (examine the debug_backtrace()) but that method does not work in PHP5. references:
30423
37684
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edit: an example of late static binding in PHP 5.3 (mentioned in comments). note there are potential problems in it's current implementat...
Output to the same line overwriting previous output?
...
Here's code for Python 3.x:
print(os.path.getsize(file_name)/1024+'KB / '+size+' KB downloaded!', end='\r')
The end= keyword is what does the work here -- by default, print() ends in a newline (\n) character, but this can be replaced with a different string. In this case, endi...
How to import multiple .csv files at once?
...olutions in other answers using things like do.call(rbind,...), dplyr::bind_rows() or data.table::rbindlist().
If you really want each data frame in a separate object, even though that's often inadvisable, you could do the following with assign:
temp = list.files(pattern="*.csv")
for (i in 1:lengt...
Downloading Java JDK on Linux via wget is shown license page instead
...e.com/otn-pub/java/jdk/14.0.1+7/664493ef4a6946b186ff29eb326336a2/jdk-14.0.1_linux-x64_bin.rpm -O ~/Downloads/jdk-14.0.1_linux-x64_bin.rpm
PS: Alf added this ( me ) :-) this, I couldn't figured out how to just commented at the end... Enjoy it.
UPDATED FOR Oracle JDK 11
wget --no-check-certificate -c...
MySQL, Check if a column exists in a table with SQL
...LIKE 'fieldname';
With PHP it would be something like...
$result = mysql_query("SHOW COLUMNS FROM `table` LIKE 'fieldname'");
$exists = (mysql_num_rows($result))?TRUE:FALSE;
share
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improve this...
Reimport a module in python while interactive
...from the importlib library instead:
import importlib
importlib.reload(some_module)
If you are using python 3.2 or 3.3 you should:
import imp
imp.reload(module)
instead. See http://docs.python.org/3.0/library/imp.html#imp.reload
If you are using ipython, definitely consider using the autor...
How do I get an animated gif to work in WPF?
...e gif has 10 frames per second.
class GifImage : Image
{
private bool _isInitialized;
private GifBitmapDecoder _gifDecoder;
private Int32Animation _animation;
public int FrameIndex
{
get { return (int)GetValue(FrameIndexProperty); }
set { SetValue(FrameIndexProp...
Comma in C/C++ macro
...ose the macro argument in parentheses:
FOO((std::map<int, int>), map_var);
The problem is then that the parameter remains parenthesized inside the macro expansion, which prevents it being read as a type in most contexts.
A nice trick to workaround this is that in C++, you can extract a typ...