There is a maximum capacity an integer can store. And when you go over that limit, it will loop back to the negative side. For int, it is 2147483647
int x = int.MaxValue; //MaxValue is 2147483647
x = unchecked(x + 1); //make operation explicitly unchecked so that the ...
Overflow also happens during the operation. In the following example, x is an int, 1 is an int by default. Therefore addition is an int addition. And the result will be an int. And it will overflow.
int x = int.MaxValue; //MaxValue is 2147483647
long y = x + 1; //...
SQL aliases are used to temporarily rename a table or a column. They are generally used to improve readability.
Query
SELECT username AS val FROM stack;
SELECT username val FROM stack;
(Note: AS is syntactically optional.)
Result
+-------+
| val |
+-------+
| admin |
| stack |
+----...
It's also possible to use data binding within your RecyclerView Adapter.
Data model
public class Item {
private String name;
public String getName() {
return name;
}
}
XML Layout
<TextView
android:layout_width="wrap_content"
android:layou...
With the ~ selector, you can easily implement a global accessible boolean without using JavaScript.
Add boolean as a checkbox
To the very beginning of your document, add as much booleans as you want with a unique id and the hidden attribute set:
<input type="checkbox" id="sideba...
An existing working copy can be quickly transformed to reflect the contents of a different branch in the same repository. For example, you might have a working copy of the trunk and now need to work on a development branch. Instead of checking out a completely new working copy (which can waste a l...
A Subversion repository can be configured so that certain contents or commands are only accessible to certain users. In order to access this restricted content, you will need to specify a username and password.
Your username and password can be specified directly as part of the command:
$ svn che...
Running svn log will show you all the commit messages, you probably want to review only certain revisions.
View the n most recent revisions:
svn log -n
View a specific revision:
svn log -c rXXX
View the paths affected:
svn log -v -c rXXX
The key in vectorizing R code, is to reduce or eliminate "by row operations" or method dispatching of R functions.
That means that when approaching a problem that at first glance requires "by row operations", such as calculating the means of each row, one needs to ask themselves...
using System.Threading;
class MainClass {
static void Main() {
var thread = new Thread(Secondary);
thread.Start("SecondThread");
}
static void Secondary(object threadName) {
System.Console.WriteLine("Hello World from thread: " + thread...
Sometimes, you want your threads to simultaneously share data. When this happens it is important to be aware of the code and lock any parts that could go wrong. A simple example of two threads counting is shown below.
Here is some dangerous (incorrect) code:
using System.Threading;
class MainCl...
Given a file using ; as a column delimiter. Permuting the first and the second column is accomplished by
awk -F';' -v 'OFS=;' '{ swap = $2; $2 = $1; $1 = swap; print }'
For example we have WordCountService with countWords method:
class WordCountService {
def countWords(url: String): Map[String, Int] = {
val sparkConf = new SparkConf().setMaster("spark://somehost:7077").setAppName("WordCount"))
val sc = new SparkContext(sp...
It is a good practice to provide expression string arguments as braced strings. The heading "Double Substitution" outlines important reasons behind the same.
The expr command evaluates an operator-based expression string to calculate a value. This string is constructed from the arguments ...
When the view controller is presented within a tab bar controller, you can access the tab bar controller like this:
Swift
let tabBarController = viewController.tabBarController
Objective-C
UITabBarController *tabBarController = self.tabBarController;
When the view controller is part on an n...
Parameters
The first 4 parameters are passed in (in order) RCX, RDX, R8 and R9.
XMM0 to XMM3 are used to pass floating point parameters.
Any further parameters are passed on the stack.
Parameters larger than 64bit are passed by address.
Spill Space
Even if the function uses less than 4 paramet...
