JavaScript typedArray.filter() with Example

The Javascript typedArray.filter() is an inbuilt function in javascript that is used to form a new typedArray with the elements which satisfy the test implemented by the function provided. 

Syntax:

typedarray.filter(callback)

Parameters: It takes the parameter “callback” function which checks each element of the typedArray satisfied by the condition provided. The callback function takes three parameters that are specified below-

• element: It is the value of the element.
• index: It is the index of the element.
• array: It is the array that is being traversed.

Return value: It returns a new typedarray with the elements that satisfy the test. 

JavaScript example to show the working of this function:

Example 1: This example shows the use of the typedArray.filter() method in Javascript.

javascript

<script>
    // Calling isNegative function to check
    // elements of the typedArray
    function isNegative(element, index, array)
    {
        return element < 0;
    }

    // Created some typedArrays.
    const A = new Int8Array([ -10, 20, -30, 40, -50 ]);
    const B = new Int8Array([ 10, 20, -30, 40, -50 ]);
    const C = new Int8Array([ -10, 20, -30, 40, 50 ]);
    const D = new Int8Array([ -10, 20, 30, 40, -50 ]);

    // Calling filter() function to check condition
    // provided by its parameter
    const a = A.filter(isNegative);
    const b = B.filter(isNegative);
    const c = C.filter(isNegative);
    const d = D.filter(isNegative);

    // Printing the filtered typedArray
    console.log(a);
    console.log(b);
    console.log(c);
    console.log(d);
</script>

Output:

-10,-30,-50
-30,-50
-10,-30
-10,-50