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Using i and j as variables in Matlab
...oop 1 billion times show no statistical difference in timing). For all we know there is special code to handle exactly this and using variables other than i and j (and k?) is actually slightly slower. And differences that do exist are miniscule to non-existent in real life. There simply is no reason...
What does $$ (dollar dollar or double dollar) mean in PHP?
...
EDIT after @Jhonny's comment :
Doing a $$$ ?
Well, the best way to know is to try ;-)
So, let's try this portion of code :
$real_variable = 'test';
$name = 'real_variable';
$name_of_name = 'name';
echo $name_of_name . '<br />';
echo $$name_of_name . '<br />';
echo $$$name_of_na...
Is there a software-engineering methodology for functional programming? [closed]
... captured as higher-order functions. For example, the Visitor pattern is known in the functional world as a "fold" (or if you are a pointy-headed theorist, a "catamorphism"). In functional languages, data types are mostly trees or tuples, and every tree type has a natural catamorphism associated w...
When should null values of Boolean be used?
...n column in a database, for example). The null value might mean "we don't know if it's true or false" in this context.
each time a method needs an Object as argument, and you need to pass a boolean value. For example, when using reflection or methods like MessageFormat.format().
...
How to cancel a Task in await?
...
Wow great info! That worked perfectly, now I need to figure out how to handle the exception in the async method. Thanks man! I'll read the stuff you suggested.
– Carlo
Apr 13 '12 at 2:48
...
ORDER BY the IN value list
... it has to be spread: in mySQL this can be done much simpler, but I don't know if it works in other SQL.
SELECT * FROM `comments`
WHERE `comments`.`id` IN ('12','5','3','17')
ORDER BY FIELD(`comments`.`id`,'12','5','3','17')
...
dplyr summarise: Equivalent of “.drop=FALSE” to keep groups with zero length in output
... 0
# Turn group2 into a factor
iris$group2 = factor(iris$group2)
# Now all possible combinations of Species and group2 are included in the output,
# whether present in the data or not
iris %>% group_by(Species, group2, .drop=FALSE) %>% tally
#> Species group2 n
#> ...
Random date in C#
...he adviced - put the variable out of the method and put all in class. Plus now the time is random too. Here is the result.
class RandomDateTime
{
DateTime start;
Random gen;
int range;
public RandomDateTime()
{
start = new DateTime(1995, 1, 1);
gen = new Random(...
How do I intercept a method call in C#?
...<b>" + Message + "</b></span>");
return;
}
Now I can have the check at run time without the dependency injection...
No gotchas in site :)
Hopefully you will agree that this is less weight then a AOP Framework or deriving from MarshalByRefObject or using remoting or ...
Android Log.v(), Log.d(), Log.i(), Log.w(), Log.e() - When to use each one?
... stuff happens. Use this tag in places like inside a catch statement. You know that an error has occurred and therefore you're logging an error.
Log.w: Use this when you suspect something shady is going on. You may not be completely in full on error mode, but maybe you recovered from some unexpected...