Tutorial by Examples: g

Quantitative data is often read in as strings that must be converted to numeric types before processing. The types of all list items can be converted with either a List Comprehension or the map() function. # Convert a list of strings to integers. items = ["1","2","3",...

A deadlock is what occurs when two or more threads are waiting for eachother to complete or to release a resource in such a way that they wait forever. A typical scenario of two threads waiting on eachother to complete is when a Windows Forms GUI thread waits for a worker thread and the worker thre...

To draw a vector SVG image, the operation is not different from a raster image : You first need to load your SVG image into an HTMLImage element, then use the drawImage() method. var image = new Image(); image.onload = function(){ ctx.drawImage(this, 0,0); } image.src = "someFile.SVG&...

This is a nice trick to add a link to code, so it will be easy to jump to the code that issued the log. With the following code, this call: MyLogger.logWithLink("MyTag","param="+param); Will result in: 07-26...012/com.myapp D/MyTag: MyFrag:onStart(param=3) (MyFrag.java:236...

Current updates the branch on the remote repository that shares a name with the current working branch. git config push.default current Simple pushes to the upstream branch, but will not work if the upstream branch is called something else. git config push.default simple Upstream pushes to t...

This is the basic way to insert data from another table with the SELECT statement. INSERT INTO `tableA` (`field_one`, `field_two`) SELECT `tableB`.`field_one`, `tableB`.`field_two` FROM `tableB` WHERE `tableB`.clmn <> 'someValue' ORDER BY `tableB`.`sorting_clmn`; You can...

git push --tags Pushes all of the git tags in the local repository that are not in the remote one.

When using the interactive interpreter, you might want to reload a module. This can be useful if you're editing a module and want to import the newest version, or if you've monkey-patched an element of an existing module and want to revert your changes. Note that you can't just import the module ag...

To hide the blinking caret, you need to override caretRectForPosition of a UITextField and return CGRectZero. Swift 2.3 < public override func caretRectForPosition(position: UITextPosition) -> CGRect { return CGRectZero } Swift 3 override func caretRect(for position: UITextPositio...

We can change the style of the placeholder by setting attributedPlaceholder (a NSAttributedString). var placeholderAttributes = [String: AnyObject]() placeholderAttributes[NSForegroundColorAttributeName] = color placeholderAttributes[NSFontAttributeName] = font if let placeholder = textField.p...

Reflection is useful but fragile. Consider this: let mi = typeof<System.String>.GetMethod "StartsWith" The problems with this kind of code are: The code doesn't work because there are several overloads of String.StartsWith Even if there wouldn't be any overloads right now la...

Starting a File Chooser Activity public void showFileChooser() { Intent intent = new Intent(Intent.ACTION_GET_CONTENT); // Update with mime types intent.setType("*/*"); // Update with additional mime types here using a String[]. intent.putExtra(Intent.EXTRA_M...

Here is a basic example form with one required text field and one submit button, which submits to a custom function: class Page_Controller extends ContentController { private static $allowed_actions = array( 'ExampleForm' ); public function ExampleForm() { $fiel...

Use the os.getcwd() function: print(os.getcwd())

The os module provides an interface to determine what type of operating system the code is currently running on. os.name This can return one of the following in Python 3: posix nt ce java More detailed information can be retrieved from sys.platform

os.chmod(path, mode) where mode is the desired permission, in octal.

Create a DATABASE. Note that the shortened word SCHEMA can be used as a synonym. CREATE DATABASE Baseball; -- creates a database named Baseball If the database already exists, Error 1007 is returned. To get around this error, try: CREATE DATABASE IF NOT EXISTS Baseball; Similarly, DROP DATA...

Arrays can be compared for equality with the aptly named isEqualToArray: method, which returns YES when both arrays have the same number of elements and every pair pass an isEqual: comparison. NSArray *germanMakes = @[@"Mercedes-Benz", @"BMW", @"Porsche", ...

The AUROC is one of the most commonly used metric to evaluate a classifier's performances. This section explains how to compute it. AUC (Area Under the Curve) is used most of the time to mean AUROC, which is a bad practice as AUC is ambiguous (could be any curve) while AUROC is not. Overview – Abb...

String concatenation is when you combine two or more strings into a single string variable. String concatenation is performed with the & symbol. Dim one As String = "Hello " Dim two As String = "there" Dim result As String = one & two Non-string values will be conv...