JavaScript | typedArray.from() with Examples
The typedArray.from() is an inbuilt function in JavaScript which is used to construct a new typedArray from a normal array or any iterable object.
List of different typedArrays are specified below-
- Int8Array();
- Uint8Array();
- Uint8ClampedArray();
- Int16Array();
- Uint16Array();
- Int32Array();
- Uint32Array();
- Float32Array();
- Float64Array();
Syntax:
Hey geek! The constant emerging technologies in the world of web development always keeps the excitement for this subject through the roof. But before you tackle the big projects, we suggest you start by learning the basics. Kickstart your web development journey by learning JS concepts with our JavaScript Course. Now at it's lowest price ever!
typedArray.from(source, mapFn, thisArg)
Parameters: It accepts three parameters which are specified below-
- source: It is a normal array or any iterable object for converting to a typedArray.
- mapFn: It is optional and it is map function to call on every element of the typedArray.
- thisArg: It is optional and it is the value to be used while executing mapFn function.
Return value: It returns a new typedArray instance.
JavaScript code to show the working of this function:
Code #1:
<script> // Constructing an iterable object var a = new Set([ 5, 10, 15, 20, 25 ]); var b = new Set([ 1, 2, 3, 4, 5 ]); var c = new Set([ 1, 3, 5, 7, 9 ]); var d = new Set([ 2, 4, 6, 8, 10 ]); // Calling from() function A = Uint8Array.from(a); B = Uint8Array.from(b); C = Uint8Array.from(c); D = Uint8Array.from(d); // Printing new typedArray instance document.write(A + "<br>"); document.write(B + "<br>"); document.write(C + "<br>"); document.write(D); </script> |
Output:
5, 10, 15, 20, 25 1, 2, 3, 4, 5 1, 3, 5, 7, 9 2, 4, 6, 8, 10
Code #2:
<script> // Calling from() function A = Uint16Array.from('123456'); B = Uint16Array.from('80397418327'); // Printing new typedArray instance document.write(A + "<br>"); document.write(B + "<br>"); </script> |
Output:
1, 2, 3, 4, 5, 6 8, 0, 3, 9, 7, 4, 1, 8, 3, 2, 7
Code #3:
<script> // Constructing an iterable object var a = new Set([ 5, 10, 15, 20, 25 ]); var b = new Set([ 1, 2, 3, 4, 5 ]); var c = new Set([ 1, 3, 5, 7, 9 ]); var d = new Set([ 2, 4, 6, 8, 10 ]); // Calling from() function A = Uint8Array.from(a, x => x + 1); B = Uint8Array.from(b, x => x + 2); C = Uint8Array.from(c, x => x * 2); D = Uint8Array.from(d); // Printing new typedArray instance document.write(A + "<br>"); document.write(B + "<br>"); document.write(C + "<br>"); document.write(D); </script> |
Output:
6, 11, 16, 21, 26 3, 4, 5, 6, 7 2, 6, 10, 14, 18 2, 4, 6, 8, 10
