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Why are variables “i” and “j” used for counters?
...ming that the summation notation arose at around the same time, the German-based notation would be expected—and the German word for index is Index, which also begins with an i. And I can't think of many letters which are particularly hard to write on a chalkboard. Well, except ξ :-)
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How to sort the result from string_agg()
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Relational Database is based in part on mathematical sets, and this is reflected in the fact that a basic principle in SQL is that row order is not significant. Even if you were to include an ORDER BY clause in the sub query, the FROM claus...
Specify pane percentage in tmuxinator project
...e to use the layout: line from the output unaltered in tmuxinator.conf
So based on the output from your gist:
0: tmux [208x73] [layout b147,208x73,0,0[208x62,0,0,208x10,0,63{104x10,0,63,103x10,105,63}]] (active)
The relevant section of the tmuxinator conf file should be:
- editor:
layo...
Rails: where does the infamous “current_user” come from?
..., it's something like:
class ApplicationController < ActionController::Base
def current_user
return unless session[:user_id]
@current_user ||= User.find(session[:user_id])
end
end
This assumes that the User class exists, e.g. #{Rails.root}/app/models/user.rb.
Updated: avoid additi...
How can one use multi threading in PHP applications
... a web server environment. Threading in PHP should therefore remain to CLI-based applications only.
Simple Test
#!/usr/bin/php
<?php
class AsyncOperation extends Thread {
public function __construct($arg) {
$this->arg = $arg;
}
public function run() {
if ($this...
Mockito: List Matchers with generics
...List<Bar>>any(List.class)));
Java 8 newly allows type inference based on parameters, so if you're using Java 8, this may work as well:
when(mock.process(Matchers.any()));
Remember that neither any() nor anyList() will apply any checks, including type or null checks. In Mockito 2.x, any...
Best way to trim strings after data entry. Should I create a custom model binder?
...r entered string fields to be trimmed before they're inserted into the database. And since I have many data entry forms, I'm looking for an elegant way to trim all strings instead of explicitly trimming every user supplied string value. I'm interested to know how and when people are trimming stri...
Difference between ObservableCollection and BindingList
...ervableCollection<T> is typically derived for the same reason as its base Collection<T> class: for customizing add/remove items (eg. in a data model collection) rather than adjusting binding features.
Copy vs. wrapping
Both ObservableCollection<T> and BindingList<T> have a...
Difference between webdriver.Dispose(), .Close() and .Quit()
... I also noticed that the IEDrivers that are used for working with IE based automation does not exit if you use driver.close() method. I had to use driver.quit() to terminate it. It is because the quit() method also appears to clean up resources unlike close(), although, in my example, I have a...
Get margin of a View
...in;
edit:
perhaps ViewGroup.MarginLayoutParams will work for you. It's a base class for other LayoutParams.
ViewGroup.MarginLayoutParams lp = (ViewGroup.MarginLayoutParams) view.getLayoutParams();
http://developer.android.com/reference/android/view/ViewGroup.MarginLayoutParams.html
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