Return the index of the first element which equals a provided search element according to the same value algorithm.
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> Return the index of the first element which equals a provided search element according to the [SameValue Algorithm][@stdlib/assert/is-same-value].
``bash`
npm install @stdlib/array-base-index-of-same-value
`javascript`
var indexOfSameValue = require( '@stdlib/array-base-index-of-same-value' );
#### indexOfSameValue( x, searchElement, fromIndex )
Returns the index of the first element which equals a provided search element according to the [SameValue Algorithm][@stdlib/assert/is-same-value].
`javascript
var x = [ 1, 2, 3, 4, 5, 6 ];
var idx = indexOfSameValue( x, 3, 0 );
// returns 2
`
If the function is unable to find an element which equals a provided search element, the function returns -1.
`javascript
var x = [ 1, 2, 3, 4, 5, 6 ];
var idx = indexOfSameValue( x, 7, 0 );
// returns -1
`
To begin searching from specific index, provide a non-zero fromIndex argument.
`javascript
var x = [ 1, 1, 2, 1, 2, 3, 3 ];
var idx = indexOfSameValue( x, 2, 3 );
// returns 4
`
If fromIndex is less than zero, the starting index is resolved relative to the last array element, with the last array element corresponding to fromIndex = -1.
`javascript
var x = [ 1, 1, 2, 1, 2, 3, 3 ];
var idx = indexOfSameValue( x, 2, -4 );
// returns 4
`
- The function performs a linear scan and returns immediately upon finding a match.
- When searching for a search element, the function checks for equality using the [SameValue Algorithm][@stdlib/assert/is-same-value] as specified in ECMAScript 5. As a consequence, NaN values are considered equal, and -0 and +0 are considered distinct.
`javascript
var indexOfSameValue = require( '@stdlib/array-base-index-of-same-value' );
var x = [ 'foo', 'bar', 'beep', 'boop', 'foo', 'bar' ];
var idx = indexOfSameValue( x, 'beep', 0 );
// returns 2
idx = indexOfSameValue( x, 'bop', 0 );
// returns -1
idx = indexOfSameValue( x, 'foo', 1 );
// returns 4
idx = indexOfSameValue( x, 'foo', -4 );
// returns 4
idx = indexOfSameValue( x, 'foo', 5 );
// returns -1
`
*
This package is part of [stdlib][stdlib], a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.
For more information on the project, filing bug reports and feature requests, and guidance on how to develop [stdlib][stdlib], see the main project [repository][stdlib].
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---
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