npm package: @stdlib/blas-ext-base-gjoin
Description: Return a string created by joining strided array elements using a specified separator.
Author: The Stdlib Authors
Latest version: 0.1.1

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# gjoin

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> Return a string created by joining strided array elements using a specified separator.

<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->

<section class="intro">

</section>

<!-- /.intro -->

<!-- Package usage documentation. -->

<section class="installation">

## Installation

```bash
npm install @stdlib/blas-ext-base-gjoin
```

</section>

<section class="usage">

## Usage

```javascript
var gjoin = require( '@stdlib/blas-ext-base-gjoin' );
```

#### gjoin( N, separator, x, strideX )

Returns a string created by joining strided array elements using a specified separator.

```javascript
var x = [ 1.0, 2.0, 3.0, 4.0 ];

var str = gjoin( x.length, ',', x, 1 );
// returns '1,2,3,4'
```

The function has the following parameters:

-   **N**: number of indexed elements.
-   **separator**: separator.
-   **x**: input array.
-   **strideX**: stride length.

The `N` and stride parameters determine which elements in the strided array are accessed at runtime. For example, to join every other element:

```javascript
var x = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ];

var str = gjoin( 3, '-', x, 2 );
// returns '1-3-5'
```

Note that indexing is relative to the first index. To introduce an offset, use [`typed array`][mdn-typed-array] views.

```javascript
var Float64Array = require( '@stdlib/array-float64' );

// Initial array:
var x0 = new Float64Array( [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ] );

// Create an offset view:
var x1 = new Float64Array( x0.buffer, x0.BYTES_PER_ELEMENT*1 ); // start at 2nd element

// Join elements:
var str = gjoin( 3, '|', x1, 2 );
// returns '2|4|6'
```

#### gjoin.ndarray( N, separator, x, strideX, offsetX )

Returns a string created by joining strided array elements using a specified separator and alternative indexing semantics.

```javascript
var x = [ 1.0, 2.0, 3.0, 4.0 ];

var str = gjoin.ndarray( x.length, ',', x, 1, 0 );
// returns '1,2,3,4'
```

The function has the following additional parameters:

-   **offsetX**: starting index.

While [`typed array`][mdn-typed-array] views mandate a view offset based on the underlying buffer, the offset parameter supports indexing semantics based on a starting index. For example, to access only the last three elements of the strided array:

```javascript
var x = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ];

var str = gjoin.ndarray( 3, '|', x, 1, x.length-3 );
// returns '4|5|6'
```

</section>

<!-- /.usage -->

<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->

<section class="notes">

## Notes

-   If `N <= 0`, both functions return an empty string.
-   If an array element is either `null` or `undefined`, both functions will serialize the element as an empty string.
-   Both functions support array-like objects having getter and setter accessors for array element access (e.g., [`@stdlib/array-base/accessor`][@stdlib/array/base/accessor]).

</section>

<!-- /.notes -->

<!-- Package usage examples. -->

<section class="examples">

## Examples

<!-- eslint no-undef: "error" -->

```javascript
var discreteUniform = require( '@stdlib/random-array-discrete-uniform' );
var gjoin = require( '@stdlib/blas-ext-base-gjoin' );

var x = discreteUniform( 10, -100, 100, {
    'dtype': 'generic'
});
console.log( x );

var out = gjoin( x.length, ' | ', x, 1 );
console.log( out );
```

</section>

<!-- /.examples -->

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</section>

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* * *

## Notice

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].

#### Community

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---

## License

See [LICENSE][stdlib-license].


## Copyright

Copyright &copy; 2016-2026. The Stdlib [Authors][stdlib-authors].

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