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What is the difference between null and undefined in JavaScript?
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In JavaScript, undefined means a variable has been declared but has not yet been assigned a value, such as:
var TestVar;
alert(TestVar); //shows undefined
alert(typeof TestVar); //shows undefined
null is an assignment value. It can be assigned to ...
CSS: How to have position:absolute div inside a position:relative div not be cropped by an overflow:
...ext/css">
/* Positioning */
#box1 { overflow: hidden }
#box2 { position: absolute }
#box3 { position: absolute; top: 10px }
/* Styling */
#box1 { background: #efe; padding: 5px; width: 125px }
#box2 { background...
Catching error codes in a shell pipe
... @n2liquid-GuilhermeVieira Btw, by "different variations", I specifically meant, remove one or both of the set (for 4 different versions total), and see how that affects the output of the last echo.
– hyde
Nov 1 '14 at 20:33
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PHP 5: const vs static
...oint that should be made is that a const is always static and public. This means that you can access the const from within the class like so:
class MyClass
{
const MYCONST = true;
public function test()
{
echo self::MYCONST;
}
}
From outside the class you would acces...
How do you check whether a number is divisible by another number (Python)?
...mply use % Modulus operator to check divisibility.
For example: n % 2 == 0 means n is exactly divisible by 2 and n % 2 != 0 means n is not exactly divisible by 2.
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What is the difference between Ruby 1.8 and Ruby 1.9
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Or did you mean Happy to help? Please edit accordingly. Or remove it, if your happiness/hopefulness counts for all your answers. ;-)
– Chris Wesseling
Apr 2 '13 at 14:09
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What is the default access modifier in Java? [duplicate]
...difier (package-private) just as with top-level classes, and with the same meaning.
Full story you can read here (Which I wrote recently):
http://codeinventions.blogspot.com/2014/09/default-access-modifier-in-java-or-no.html
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How to select the row with the maximum value in each group
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A dplyr solution:
library(dplyr)
ID <- c(1,1,1,2,2,2,2,3,3)
Value <- c(2,3,5,2,5,8,17,3,5)
Event <- c(1,1,2,1,2,1,2,2,2)
group <- data.frame(Subject=ID, pt=Value, Event=Event)
group %>%
group_by(Subject) %>%
summarize(max.pt = max(...
MySQL Select all columns from one table and some from another table
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SELECT table1.*, table2.col1, table2.col3 FROM table1 JOIN table2 USING(id)
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Google OAuth 2 authorization - Error: redirect_uri_mismatch
...m/apis/console I have registered my application, set up generated Client ID: and Client Secret to my app and tried to log in with Google.
Unfortunately, I got the error message:
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