count() will return the number of times and element appears in an array. In the following example we see that the value 3 occurs twice.
my_array = array('i', [1,2,3,3,5])
my_array.count(3)
# 2
When you need a Python list object, you can utilize the tolist() method to convert your array to a list.
my_array = array('i', [1,2,3,4,5])
c = my_array.tolist()
# [1, 2, 3, 4, 5]
This is a relatively common mistake: You created an rect element, in a bar chart for instance, and you want to add a text label (let's say, the value of that bar). So, using the same variable that you used to append the rect and define its x and y position, you append your text element. Very logic, ...
The simplest way to understand creating and modifying SVG elements is to operate on the elements using the DOM Level 2 Core interfaces, as you would with HTML or XML.
It is imperative that the elements created from JavaScript are created in the same namespace declared in the SVG element - in this e...
Using the mouse to drag an SVG element (or group of elements) can be accomplished by:
Adding mousedown handler to starts the drag: adding a translation on the element to use during dragging (if needed), tracking mousemove events, and adding a mouseup handler to end the drag.
During mousemove, tr...
Many bugs in knockout data binds are caused by undefined properties in a viewmodel. Knockout has two handy methods to retrieve the binding context of an HTML element:
// Returns the binding context to which an HTMLElement is bound
ko.contextFor(element);
// Returns the viewmodel to which ...
public static async Task<WriteableBitmap> RenderUIElement(UIElement element)
{
var bitmap = new RenderTargetBitmap();
await bitmap.RenderAsync(element);
var pixelBuffer = await bitmap.GetPixelsAsync();
var pixels = pixelBuffer.ToArray();
var writeableBitmap = new W...
C#
Suppose you want to test that when you hover over an element, a drop list is displayed. You may want to check the contents of this list, or perhaps select an option from the list.
First create an Action, to hover over the element (e.g. my element has link text "Admin"):
Actions mouse...
In this example we create a new list element with the text "new text", and select the first unordered list, and its first list element.
let newElement = document.createElement("li");
newElement.innerHTML = "new text";
let parentElement = document.querySelector(&quo...
In this example we create a new list element with the text "new text", and select the first unordered list, and its first list element.
let newElement = document.createElement("li");
newElement.innerHTML = "new text";
let parentElement = document.querySelector(&quo...
An element can be removed by calling remove() on it. Alternatively, one can call removeChild() on its parent. removeChild() has better browser support than remove().
element.remove();
element, and all its childnodes, are removed from the DOM.
parentElement.removeChild(element);
element...
Less doesn't put any restrictions on the number of times the parent selector (&) can be used in a complex selector and so, we can use it more than once like in the below examples to select sibling elements without the need to repeat the selector.
.demo {
border: 1px solid black; /* add borde...
Inserting elements is simple:
> let m = Map.singleton "Alex" 31
fromList [("Alex",31)]
> Map.insert "Bob" 99 m
fromList [("Alex",31),("Bob",99)]
To remove an element from a map use the .delete() method.
map.delete(key);
Example:
const map = new Map([[1, 2], [3, 4]]);
console.log(map.get(3)); // 4
map.delete(3);
console.log(map.get(3)); // undefined
This method returns true if the element existed and has been removed, otherwise fal...
Use .get(key) to get value by key and .set(key, value) to assign a value to a key.
If the element with the specified key doesn't exist in the map, .get() returns undefined.
.set() method returns the map object, so you can chain .set() calls.
const map = new Map();
console.log(map.get(1)); // und...
This example is about replacing a List element while ensuring that the replacement element is at the same position as the element that is replaced.
This can be done using these methods:
set(int index, T type)
int indexOf(T type)
Consider an ArrayList containing the elements "Program sta...
To check if an element with a specified key exits in a WeakMap, use the .has() method. It returns true if it exits, and otherwise false.
const obj1 = {},
obj2 = {};
const weakmap = new WeakMap([[obj1, 7]]);
console.log(weakmap.has(obj1)); // true
console.log(weakmap.has(obj2)); // false...
