Tutorial by Examples: e

In helloWorld.sh #!/bin/bash # Define a function greet greet () { echo "Hello World!" } # Call the function greet greet In running the script, we see our message $ bash helloWorld.sh Hello World! Note that sourcing a file with functions makes them available in your ...

$.ajax({ url: 'https://api.dropboxapi.com/2/sharing/add_folder_member', type: 'POST', processData: false, data: JSON.stringify({"shared_folder_id": "84528192421","members": [{"member": {".tag": "email","email":...

// This creates an array with 5 values. const int array[] = { 1, 2, 3, 4, 5 }; #ifdef BEFORE_CPP11 // You can use `sizeof` to determine how many elements are in an array. const int* first = array; const int* afterLast = first + sizeof(array) / sizeof(array[0]); // Then you can iterate ov...

An if statement checks whether a Bool condition is true: let num = 10 if num == 10 { // Code inside this block only executes if the condition was true. print("num is 10") } let condition = num == 10 // condition's type is Bool if condition { print("num is 10&...

Optionals must be unwrapped before they can be used in most expressions. if let is an optional binding, which succeeds if the optional value was not nil: let num: Int? = 10 // or: let num: Int? = nil if let unwrappedNum = num { // num has type Int?; unwrappedNum has type Int print(&quo...

To allow the use of in for custom classes the class must either provide the magic method __contains__ or, failing that, an __iter__-method. Suppose you have a class containing a list of lists: class ListList: def __init__(self, value): self.value = value # Create a set of al...

var favoriteColors: Set = ["Red", "Blue", "Green"] //favoriteColors = {"Blue", "Green", "Red"} You can use the insert(_:) method to add a new item into a set. favoriteColors.insert("Orange") //favoriteColors = {"Red&q...

from collections import Counter c = Counter(["a", "b", "c", "d", "a", "b", "a", "c", "d"]) c # Out: Counter({'a': 3, 'b': 2, 'c': 2, 'd': 2}) c["a"] # Out: 3 c[7] # not in the list (7 oc...

Counting the keys of a Mapping isn't possible with collections.Counter but we can count the values: from collections import Counter adict = {'a': 5, 'b': 3, 'c': 5, 'd': 2, 'e':2, 'q': 5} Counter(adict.values()) # Out: Counter({2: 2, 3: 1, 5: 3}) The most common elements are avaiable by the m...

alist = [1, 2, 3, 4, 1, 2, 1, 3, 4] alist.count(1) # Out: 3 atuple = ('bear', 'weasel', 'bear', 'frog') atuple.count('bear') # Out: 2 atuple.count('fox') # Out: 0

astring = 'thisisashorttext' astring.count('t') # Out: 4 This works even for substrings longer than one character: astring.count('th') # Out: 1 astring.count('is') # Out: 2 astring.count('text') # Out: 1 which would not be possible with collections.Counter which only counts single char...

var favoriteColors: Set = ["Red", "Blue", "Green"] //favoriteColors = {"Blue", "Green", "Red"} You can use the contains(_:) method to check whether a set contains a value. It will return true if the set contains that value. if favorite...

To load jQuery from the official CDN, go to the jQuery website. You'll see a list of different versions and formats available. Now, copy the source of the version of jQuery, you want to load. Suppose, you want to load jQuery 2.X, click uncompressed or minified tag which will show you something li...

class MultiIndexingList: def __init__(self, value): self.value = value def __repr__(self): return repr(self.value) def __getitem__(self, item): if isinstance(item, (int, slice)): return self.__class__(self.value[item]) r...

Import the ElementTree object, open the relevant .xml file and get the root tag: import xml.etree.ElementTree as ET tree = ET.parse("yourXMLfile.xml") root = tree.getroot() There are a few ways to search through the tree. First is by iteration: for child in root: print(child.ta...

(Note: All examples using let are also valid for const) var is available in all versions of JavaScript, while let and const are part of ECMAScript 6 and only available in some newer browsers. var is scoped to the containing function or the global space, depending when it is declared: var x = 4; /...

When a function is declared, variables in the context of its declaration are captured in its scope. For example, in the code below, the variable x is bound to a value in the outer scope, and then the reference to x is captured in the context of bar: var x = 4; // declaration in outer scope funct...

Importing using base R Comma separated value files (CSVs) can be imported using read.csv, which wraps read.table, but uses sep = "," to set the delimiter to a comma. # get the file path of a CSV included in R's utils package csv_path <- system.file("misc", "exDIF.csv&q...

By default, a Date object is created as local time. This is not always desirable, for example when communicating a date between a server and a client that do not reside in the same timezone. In this scenario, one doesn't want to worry about timezones at all until the date needs to be displayed in lo...

Java SE 7 As the try-catch-final statement example illustrates, resource cleanup using a finally clause requires a significant amount of "boiler-plate" code to implement the edge-cases correctly. Java 7 provides a much simpler way to deal with this problem in the form of the try-with-res...