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feat: add ndarray/base/slice 
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‎lib/node_modules/@stdlib/ndarray/base/slice/README.md‎

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<!--
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@license Apache-2.0
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Copyright (c) 2023 The Stdlib Authors.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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-->
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# slice
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> Return a read-only view of an input ndarray.
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<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
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<section class="intro">
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</section>
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<!-- /.intro -->
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<!-- Package usage documentation. -->
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<section class="usage">
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## Usage
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```javascript
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var slice = require( '@stdlib/ndarray/base/slice' );
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```
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#### slice( x, slice, strict )
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Returns a **read-only** view of an input ndarray.
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```javascript
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var Slice = require( '@stdlib/slice/ctor' );
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var MultiSlice = require( '@stdlib/slice/multi' );
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var ndarray = require( '@stdlib/ndarray/ctor' );
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var ndarray2array = require( '@stdlib/ndarray/to-array' );
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var buffer = [ 1.0, 2.0, 3.0, 4.0, 5.0, 6.0 ];
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var shape = [ 3, 2 ];
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var strides = [ 2, 1 ];
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var offset = 0;
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var x = ndarray( 'generic', buffer, shape, strides, offset, 'row-major' );
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// returns <ndarray>
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var sh = x.shape;
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// returns [ 3, 2 ]
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var arr = ndarray2array( x );
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// returns [ [ 1.0, 2.0 ], [ 3.0, 4.0 ], [ 5.0, 6.0 ] ]
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var s0 = new Slice( null, null, -2 );
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var s1 = new Slice( null, null, -1 );
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var s = new MultiSlice( s0, s1 );
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// returns <MultiSlice>
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var y = slice( x, s, false );
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// returns <ndarray>
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sh = y.shape;
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// returns [ 2, 2 ]
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arr = ndarray2array( y );
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// returns [ [ 6.0, 5.0 ], [ 2.0, 1.0 ] ]
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```
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The function accepts the following arguments:
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- **x**: input ndarray.
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- **slice**: a [`MultiSlice`][@stdlib/slice/multi] instance.
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- **strict**: boolean indicating whether to enforce strict bounds checking.
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</section>
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<!-- /.usage -->
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<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
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<section class="notes">
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</section>
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<!-- /.notes -->
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<!-- Package usage examples. -->
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<section class="examples">
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## Examples
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<!-- eslint no-undef: "error" -->
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<!-- eslint-disable new-cap -->
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```javascript
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var S = require( '@stdlib/slice/ctor' );
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var E = require( '@stdlib/slice/multi' );
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var array = require( '@stdlib/ndarray/array' );
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var ndarray2array = require( '@stdlib/ndarray/to-array' );
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var zeroTo = require( '@stdlib/array/base/zero-to' );
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var slice = require( '@stdlib/ndarray/base/slice' );
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// Alias `null` to allow for more compact indexing expressions:
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var _ = null;
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// Create a linear ndarray buffer:
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var buf = zeroTo( 27 );
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// Create an ndarray:
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var x = array( buf, {
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'shape': [ 3, 3, 3 ]
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});
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// Get each matrix...
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var s1 = E( 0, _, _ );
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var y1 = slice( x, s1, false );
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// returns <ndarray>
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var a1 = ndarray2array( y1 );
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// returns [ [ 0, 1, 2 ], [ 3, 4, 5 ], [ 6, 7, 8 ] ]
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var s2 = E( 1, _, _ );
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var y2 = slice( x, s2, false );
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// returns <ndarray>
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var a2 = ndarray2array( y2 );
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// returns [ [ 9, 10, 11 ], [ 12, 13, 14 ], [ 15, 16, 17 ] ]
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var s3 = E( 2, _, _ );
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var y3 = slice( x, s3, false );
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// returns <ndarray>
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var a3 = ndarray2array( y3 );
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// returns [ [ 18, 19, 20 ], [ 21, 22, 23 ], [ 24, 25, 26 ] ]
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// Reverse all elements:
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var s = S( _, _, -1 );
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var s4 = E( s, s, s );
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var y4 = slice( x, s4, false );
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// returns <ndarray>
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var a4 = ndarray2array( y4 );
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// returns [...]
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// Get the second rows from each matrix:
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var s5 = E( _, 1, _ );
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var y5 = slice( x, s5, false );
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// returns <ndarray>
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var a5 = ndarray2array( y5 );
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// returns [ [ 3, 4, 5 ], [ 12, 13, 14 ], [ 21, 22, 23 ] ]
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// Get the second columns from each matrix:
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var s6 = E( _, _, 1 );
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var y6 = slice( x, s6, false );
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// returns <ndarray>
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var a6 = ndarray2array( y6 );
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// returns [ [ 1, 4, 7 ], [ 10, 13, 16 ], [ 19, 22, 25 ] ]
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```
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</section>
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<!-- /.examples -->
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<!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
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<section class="references">
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</section>
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<!-- /.references -->
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<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->
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<section class="related">
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</section>
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<!-- /.related -->
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<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
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<section class="links">
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[@stdlib/slice/multi]: https://github.com/stdlib-js/stdlib
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</section>
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<!-- /.links -->

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