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Event system in Python
...r methods', which is a
simple implementation of the Observer pattern.
Basically, the handler methods (callables) are stored in an array and are each called when the event 'fires'.
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The disadvantage of Observer event systems is that you can only register the handlers on the actual Ev...
How to use phpexcel to read data and insert into database?
...el_Cell::columnIndexFromString($sheet->getHighestColumn()); I am not infallible `
– Mark Baker
Jun 16 '13 at 21:48
...
When to use self over $this?
...
$x = new Y();
$x->bar();
?>
The idea is that $this->foo() calls the foo() member function of whatever is the exact type of the current object. If the object is of type X, it thus calls X::foo(). If the object is of type Y, it calls Y::foo(). But with self::foo(), X::foo() is always ...
What is the difference between 'my' and 'our' in Perl?
...
On the other hand, our variables are package variables, and thus automatically:
global variables
definitely not private
not necessarily new
can be accessed outside the package (or lexical scope) with the
qualified namespace, as $package_name::variable.
Declaring a variable with our allows you...
Upgrading PHP in XAMPP for Windows?
...a backup of your htdocs and data folder (subfolder of MySQL folder), reinstall upgraded version and replace those folders.
Note:
In case you have changed config files like PHP (php.ini), Apache (httpd.conf) or any other, please take back up of those files as well and replace them with newly install...
Comma in C/C++ macro
...his is also a problem for square brackets and braces, even though those usually occur as balanced pairs.) You can enclose 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 pr...
Why use strict and warnings?
...tify how much it helps. It should suffice to say that they help unconditionally.
– ikegami
Nov 6 '11 at 19:42
1
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Transposing a NumPy array
...of a 1D array is still a 1D array! (If you're used to matlab, it fundamentally doesn't have a concept of a 1D array. Matlab's "1D" arrays are 2D.)
If you want to turn your 1D vector into a 2D array and then transpose it, just slice it with np.newaxis (or None, they're the same, newaxis is just mor...
Adding git branch on the Bash command prompt
...
git 1.9.3 or later: use __git_ps1
Git provides a shell script called git-prompt.sh, which includes a function __git_ps1 that
prints text to add to bash PS1 prompt (includes branch name)
Its most basic usage is:
$ __git_ps1
(master)
It also takes an optional format string:
$ __g...
Fixed size queue which automatically dequeues old values upon new enques
...ur own queue, just use the inherited one. If you do as you do, you can actually do nothing else with the queue values, all other functions but your new Enqueue will still call the original queue. In other words, although this answer is marked as accepted, it's completely and utterly broken.
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