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Pandas aggregate count distinct
Let's say I have a log of user activity and I want to generate a report of total duration and the number of unique users per day.
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Search for all files in project containing the text 'querystring' in Eclipse
I work in Dreamweaver and Eclipse when developing. I think Dreamweaver has a really nice search where you can search for text within all files of your current project.
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Stretch and scale a CSS image in the background - with CSS only
I want that my background image stretch and scale depending on the browser viewport size.
22 Answers
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run main class of Maven project [duplicate]
...e main class (which doesn't require any arguments) can be run from the command-line using a maven command like:
2 Answers
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For loop example in MySQL
...ile v_counter < v_max do
insert into foo (val) values ( floor(0 + (rand() * 65535)) );
set v_counter=v_counter+1;
end while;
commit;
end #
delimiter ;
call load_foo_test_data();
select * from foo order by id;
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background-size in shorthand background property (CSS3)
I'm trying to mix background-image and background-size properties in a shorthanded background property. Based on W3C documentation background-size should come after background-position property separated with an slash( / ).
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Design Patterns: Factory vs Factory method vs Abstract Factory
...uctor".
Let's say you want to be able to create two kinds of Fruit: Apple and Orange.
Factory
Factory is "fixed", in that you have just one implementation with no subclassing. In this case, you will have a class like this:
class FruitFactory {
public Apple makeApple() {
// Code for creati...
How do I load my script into the node.js REPL?
...escribe. However, an alternative to using require it to use the .load command within the REPL, like such:
.load foo.js
It loads the file in line by line just as if you had typed it in the REPL. Unlike require this pollutes the REPL history with the commands you loaded. However, it has the adva...
How do I undo a checkout in git?
...to/file
For the entire repository working copy:
git reset --hard HEAD
And if that doesn't work, then you can look in the reflog to find your old head SHA and reset to that:
git reflog
git reset --hard <sha from reflog>
HEAD is a name that always points to the latest commit in your curr...
How do you Encrypt and Decrypt a PHP String?
...
Before you do anything further, seek to understand the difference between encryption and authentication, and why you probably want authenticated encryption rather than just encryption.
To implement authenticated encryption, you want to Encrypt then MAC. The order of encry...