Tutorial by Examples: d

With fixed pattern stri_count_fixed("babab", "b") # [1] 3 stri_count_fixed("babab", "ba") # [1] 2 stri_count_fixed("babab", "bab") # [1] 1 Natively: length(gregexpr("b","babab")[[1]]) # [1] 3 length(gregexpr(...

stri_dup("abc",3) # [1] "abcabcabc" A base R solution that does the same would look like this: paste0(rep("abc",3),collapse = "") # [1] "abcabcabc"

You can specify different application IDs or package names for each buildType or productFlavor using the applicationIdSuffix configuration attribute: Example of suffixing the applicationId for each buildType: defaultConfig { applicationId "com.package.android" minSdkVersion 17 ...

Parameters to a function can be marked as mandatory function Get-Greeting{ param ( [Parameter(Mandatory=$true)]$name ) "Hello World $name" } If the function is invoked without a value, the command line will prompt for the value: $greeting = Get-Greeting ...

A compound view is a custom ViewGroup that's treated as a single view by the surrounding program code. Such a ViewGroup can be really useful in DDD-like design, because it can correspond to an aggregate, in this example, a Contact. It can be reused everywhere that contact is displayed. This means t...

This example listens for input coming in over the serial connection, then repeats it back out the same connection. byte incomingBytes; void setup() { Serial.begin(9600); // Opens serial port, sets data rate to 9600 bps. } void loop() { // Send data only when you receive...

Glide includes two default transformations, fit center and center crop. Fit center: Glide.with(context) .load(yourUrl) .fitCenter() .into(yourView); Fit center performs the same transformation as Android's ScaleType.FIT_CENTER. Center crop: Glide.with(context) .load(yourUr...

A major problem with parallelization is the used of RNG as seeds. Random numbers by the number are iterated by the number of operations from either the start of the session or the most recent set.seed(). Since parallel processes arise from the same function, it can use the same seed, possibly causin...

To share your code you create a repository on a remote server to which you will copy your local repository. To minimize the use of space on the remote server you create a bare repository: one which has only the .git objects and doesn't create a working copy in the filesystem. As a bonus you set thi...

If there are sections of code that you are considering removing or want to temporarily disable, you can comment it out with a block comment. /* Block comment around whole function to keep it from getting used. * What's even the purpose of this function? int myUnusedFunction(void) { int i =...

Let's say we have the following structure: struct MY_STRUCT { int my_int; float my_float; }; We can define MY_STRUCT to omit the struct keyword so we don't have to type struct MY_STRUCT each time we use it. This, however, is optional. typedef struct MY_STRUCT MY_STRUCT; If we th...

Descriptive names and structure in your code help make comments unnecessary Dim ductWidth As Double Dim ductHeight As Double Dim ductArea As Double ductArea = ductWidth * ductHeight is better than Dim a, w, h a = w * h This is especially helpful when you are copying data from one ...

Good error handling prevents end users from seeing VBA runtime errors and helps the developer easily diagnose and correct errors. There are three main methods of Error Handling in VBA, two of which should be avoided for distributed programs unless specifically required in the code. On Error GoTo 0...

The .GetValueOrDefault() method returns a value even if the .HasValue property is false (unlike the Value property, which throws an exception). class Program { static void Main() { int? nullableExample = null; int result = nullableExample.GetValueOrDefault(); C...

When filtering an email address filter_var() will return the filtered data, in this case the email address, or false if a valid email address cannot be found: var_dump(filter_var('[email protected]', FILTER_VALIDATE_EMAIL)); var_dump(filter_var('notValidEmail', FILTER_VALIDATE_EMAIL)); Results: ...

When filtering a value that should be an integer filter_var() will return the filtered data, in this case the integer, or false if the value is not an integer. Floats are not integers: var_dump(filter_var('10', FILTER_VALIDATE_INT)); var_dump(filter_var('a10', FILTER_VALIDATE_INT)); var_dump(filt...

When validating that an integer falls in a range the check includes the minimum and maximum bounds: $options = array( 'options' => array( 'min_range' => 5, 'max_range' => 10, ) ); var_dump(filter_var('5', FILTER_VALIDATE_INT, $options)); var_dump(filter_var('...

When filtering a URL filter_var() will return the filtered data, in this case the URL, or false if a valid URL cannot be found: URL: example.com var_dump(filter_var('example.com', FILTER_VALIDATE_URL)); var_dump(filter_var('example.com', FILTER_VALIDATE_URL, FILTER_FLAG_SCHEME_REQUIRED)); var_du...

There are two ways you can bind a GridView. You can either manually do it by setting the DataSource property and calling DataBind(), or you can use a DataSourceControl such as a SqlDataSource. Manual Binding Create your GridView: <asp:GridView ID="gvColors" runat="server"&g...

In PHP 5.3+ and above you can utilize late static binding to control which class a static property or method is called from. It was added to overcome the problem inherent with the self:: scope resolutor. Take the following code class Horse { public static function whatToSay() { echo ...