๐Array
๐ง under construction
JS โฉ value โฉ objectโฉ built-in โฉ Array
array
is iterable
is not associated array.
inherits methods from Array.prototype, most of these methods are generic, they work correctly for any "array-like" object.
โ๏ธ array object properties vs. array elements
thery are separateโ
array's traversal and mutation operations cannot be applied to these named properties.
setting / accessing via anything other than nonnegative integers๏ผ
will not set / retrieve an array element
will set / access one of the array's object properties.
deleting an array element leaves a โholeโ in the array and does not change the arrayโs lengthโ (sparse array)
๐ธelement
๐ธelement index
๐ฐ creating arrays
๐ขarray literal
๐ฐ accessing elements
๐ฐ iterating elements
๐ฐ extending Array
other topics
๐ array-like - object that has indexes and length.
๐ sparse array - array that has "holes" in it.
๐ฐ accessing elements
push() - append element.
pop() - remove and return last element.
unshift() - prepend element.
shift() - remove and return first element.
combine elements
join - ้ฃๆฅๆๆๅ ็ด ใๅไฝตๆไธๅๅญไธฒใ
reduce((result, element, index, array) => {...}) -
reduceRight - reduce array from highest index to lowest. (from right to left)
find & search elements
Array is iterable.
bracket notation [] is used to access element.
JavaScript: The Definitive Guide > Ch. 7 Arrays
Guides โฉ Arrays โญ๏ธ
( ๐ง to be removed ... )
matrix methods (instance):
mat.transpose() - see matrix in "columns"
mat.maxElementInEachColumn() - for number matrices only.
How to get first N number of elements from an array
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