Tutorial by Examples: nd

The % wildcard appended to the beginning or end (or both) of a string will allow 0 or more of any character before the beginning or after the end of the pattern to match. Using '%' in the middle will allow 0 or more characters between the two parts of the pattern to match. We are going to use this...

When working with multi-module projects, it is helpful to centralize dependencies in a single location rather than having them spread across many build files, especially for common libraries such as the Android support libraries and the Firebase libraries. One recommended way is to separate the Gra...

First, some terminology: argument (actual parameter): the actual variable being passed to a function; parameter (formal parameter): the receiving variable that is used in a function. In Python, arguments are passed by assignment (as opposed to other languages, where arguments can be passed by...

INSERT INTO `table_name` (`index_field`, `other_field_1`, `other_field_2`) VALUES ('index_value', 'insert_value', 'other_value') ON DUPLICATE KEY UPDATE `other_field_1` = 'update_value', `other_field_2` = VALUES(`other_field_2`); This will INSERT into ta...

virtualenv is a tool to build isolated Python environments. This program creates a folder which contains all the necessary executables to use the packages that a Python project would need. Installing the virtualenv tool This is only required once. The virtualenv program may be available through yo...

A module is a file containing Python definitions and statements. Function is a piece of code which execute some logic. >>> pow(2,3) #8 To check the built in function in python we can use dir(). If called without an argument, return the names in the current scope. Else, return an alph...

NSDictionary *inventory = [NSDictionary dictionaryWithObjectsAndKeys: [NSNumber numberWithInt:13], @"Mercedes-Benz SLK250", [NSNumber numberWithInt:22], @"Mercedes-Benz E350", [NSNumber numberWithInt:19], @"BMW M3 Coupe", [NSNumber numberWithInt:16],...

If a code module does not contain Option Explicit at the top of the module, then the compiler will automatically (that is, "implicitly") create variables for you when you use them. They will default to variable type Variant. Public Sub ExampleDeclaration() someVariable = 10 ...

There are several ways to go about installing matplotlib, some of which will depend on the system you are using. If you are lucky, you will be able to use a package manager to easily install the matplotlib module and its dependencies. Windows On Windows machines you can try to use the pip package ...

Java provides, as part of the utils package, a basic pseudo-random number generator, appropriately named Random. This object can be used to generate a pseudo-random value as any of the built-in numerical datatypes (int, float, etc). You can also use it to generate a random Boolean value, or a random...

The method nextInt(int bound) of Random accepts an upper exclusive boundary, i.e. a number that the returned random value must be less than. However, only the nextInt method accepts a bound; nextLong, nextDouble etc. do not. Random random = new Random(); random.nextInt(1000); // 0 - 999 int num...

First of all, implement your view holder: implements View.OnClickListener, View.OnLongClickListener Then, register the listeners as follows: itemView.setOnClickListener(this); itemView.setOnLongClickListener(this); Next, override the listeners as follows: @Override public void onClick(Vie...

Properties are members of an object. Each named property is a pair of (name, descriptor). The name is a string that allows access (using the dot notation object.propertyName or the square brackets notation object['propertyName']). The descriptor is a record of fields defining the bevahiour of the pr...

// decode NSString *string = [[NSString alloc] initWithData:utf8Data encoding:NSUTF8StringEncoding]; // encode NSData *utf8Data = [string dataUsingEncoding:NSUTF8StringEncoding]; Some supported encodings are: NSASCIIStringEncoding NSUTF8StringEnc...

Download Qt for Linux Open Source Version Go to https://www.qt.io/download-open-source/ and click on Download Now, make sure that you are downloading the Qt installer for Linux. A file with the name qt-unified-linux-x-online.run will be downloaded, then add exec permission chmod +x qt-unified-...

Java 8 provides classes called IntSummaryStatistics, DoubleSummaryStatistics and LongSummaryStatistics which give a state object for collecting statistics such as count, min, max, sum, and average. Java SE 8 List<Integer> naturalNumbers = Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8, 9, 10); IntSu...

To make a rounded UIView, specify a cornerRadius for the view's layer. This also applies any class which inherits from UIView, such as UIImageView. Programmatically Swift Code someImageView.layoutIfNeeded() someImageView.clipsToBounds = true someImageView.layer.cornerRadius = 10 Objective-C...

In this example, we will look at a method for returning the last non-empty row in a column for a data set. This method will work regardless of empty regions within the data set. However caution should be used if merged cells are involved, as the End method will be "stopped" against a mer...

All Java exceptions are instances of classes in the Exception class hierarchy. This can be represented as follows: java.lang.Throwable - This is the base class for all exception classes. Its methods and constructors implement a range of functionality common to all exceptions. java.lang.Excep...

x = (1, 2, 3) x[0] # 1 x[1] # 2 x[2] # 3 x[3] # IndexError: tuple index out of range Indexing with negative numbers will start from the last element as -1: x[-1] # 3 x[-2] # 2 x[-3] # 1 x[-4] # IndexError: tuple index out of range Indexing a range of elements print(x[:-1]) # (1,...