Advanced Array Methods and Transformations Sum-Up
map() Method
- Purpose: Iterates over each element of the original array and applies a specified callback function to produce a new array;
- Syntax:
array.map((element, index, array) => { // Callback body });
- Key Points:
- Does not modify the original array;
- Returns a new array of the same length;
- Useful for transforming each element of an array.
filter() Method
- Purpose: Selects elements that meet a particular condition, creating a new array;
- Syntax:
array.filter((element, index, array) => { // Callback body });
- Key Points:
- Does not alter the original array;
- Returns a new array containing elements that satisfy the callback condition;
- Provides a way to filter elements based on specific criteria.
find() Method
- Purpose: Discovers and retrieves the first matching element in an array;
- Syntax:
array.find((element, index, array) => { // Callback body });
- Key Points:
- Does not alter the original array;
- Halts upon locating the initial match, returning that specific element;
- Returns
undefined
if no matching element is found.
sort() Method
- Purpose: Modifies the original array, arranging its elements in a new order;
- Syntax:
array.sort((a, b) => { // Callback body });
- Key Points:
- Transforms the original array;
- By default, arranges elements in ascending order;
- Custom sorting can be achieved using a compare function.
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SectionΒ 5. ChapterΒ 9
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Advanced Array Methods and Transformations Sum-Up
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map() Method
- Purpose: Iterates over each element of the original array and applies a specified callback function to produce a new array;
- Syntax:
array.map((element, index, array) => { // Callback body });
- Key Points:
- Does not modify the original array;
- Returns a new array of the same length;
- Useful for transforming each element of an array.
filter() Method
- Purpose: Selects elements that meet a particular condition, creating a new array;
- Syntax:
array.filter((element, index, array) => { // Callback body });
- Key Points:
- Does not alter the original array;
- Returns a new array containing elements that satisfy the callback condition;
- Provides a way to filter elements based on specific criteria.
find() Method
- Purpose: Discovers and retrieves the first matching element in an array;
- Syntax:
array.find((element, index, array) => { // Callback body });
- Key Points:
- Does not alter the original array;
- Halts upon locating the initial match, returning that specific element;
- Returns
undefined
if no matching element is found.
sort() Method
- Purpose: Modifies the original array, arranging its elements in a new order;
- Syntax:
array.sort((a, b) => { // Callback body });
- Key Points:
- Transforms the original array;
- By default, arranges elements in ascending order;
- Custom sorting can be achieved using a compare function.
Everything was clear?
Thanks for your feedback!
SectionΒ 5. ChapterΒ 9