feat: add ndarray/base/dtype-chars

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Author: kgryte

lib/node_modules/@stdlib/ndarray/base/dtype-chars/README.md

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+<!--
+
+@license Apache-2.0
+
+Copyright (c) 2025 The Stdlib Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+-->
+
+# dtypeChars
+
+> List of ndarray data type single letter character abbreviations.
+
+<!-- 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="usage">
+
+## Usage
+
+```javascript
+var dtypeChars = require( '@stdlib/ndarray/base/dtype-chars' );
+```
+
+#### dtypeChars( \[kind] )
+
+Returns a list of ndarray data type single letter character abbreviations.
+
+```javascript
+var out = dtypeChars();
+// e.g., returns [ 'r', 'j', 'c', 'z', ... ]
+```
+
+When not provided a data type "kind", the function returns an array containing the single letter character abbreviations for all support ndarray [data types][@stdlib/ndarray/dtypes]. To return the subset of data type single letter character abbreviations belonging to a specified data type kind, provide a `kind` argument.
+
+```javascript
+var out = dtypeChars( 'floating_point' );
+// returns [...]
+```
+
+The function supports the following data type kinds:
+
+-   `floating_point`: floating-point data types.
+-   `real_floating_point`: real-valued floating-point data types.
+-   `complex_floating_point`: complex-valued floating-point data types.
+-   `boolean`: boolean data types.
+-   `integer`: integer data types.
+-   `signed_integer`: signed integer data types.
+-   `unsigned_integer`: unsigned integer data types.
+-   `real`: real-valued data types.
+-   `numeric`: numeric data types.
+-   `typed`: typed data types.
+-   `integer_index`: integer index data types.
+-   `boolean_index`: boolean index data types.
+-   `mask_index`: mask index data types.
+-   `typed_index`: typed index data types.
+-   `index`: index data types.
+-   `all`: all data types.
+
+Additionally, the function supports extending the "kinds" listed above by appending an `_and_generic` suffix to the kind name (e.g., `real_and_generic`).
+
+```javascript
+var out = dtypeChars( 'floating_point_and_generic' );
+// returns [...]
+```
+
+</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">
+
+</section>
+
+<!-- /.notes -->
+
+<!-- Package usage examples. -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+```javascript
+var contains = require( '@stdlib/array/base/assert/contains' ).factory;
+var dtypeChars = require( '@stdlib/ndarray/base/dtype-chars' );
+
+var isdtypeChar = contains( dtypeChars() );
+
+var bool = isdtypeChar( 'd' );
+// returns true
+
+bool = isdtypeChar( 'k' );
+// returns true
+
+bool = isdtypeChar( 'b' );
+// returns true
+
+bool = isdtypeChar( '~' );
+// returns false
+```
+
+</section>
+
+<!-- /.examples -->
+
+<!-- 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. -->
+
+<section class="references">
+
+</section>
+
+<!-- /.references -->
+
+<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->
+
+<section class="related">
+
+</section>
+
+<!-- /.related -->
+
+<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="links">
+
+[@stdlib/ndarray/dtypes]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/ndarray/dtypes
+
+</section>
+
+<!-- /.links -->

lib/node_modules/@stdlib/ndarray/base/dtype-chars/benchmark/benchmark.js

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+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2025 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var bench = require( '@stdlib/bench' );
+var isStringArray = require( '@stdlib/assert/is-string-array' ).primitives;
+var pkg = require( './../package.json' ).name;
+var dtypeChars = require( './../lib' );
+
+
+// MAIN //
+
+bench( pkg, function benchmark( b ) {
+	var out;
+	var i;
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		out = dtypeChars();
+		if ( out.length === 0 ) {
+			b.fail( 'should return a non-empty array' );
+		}
+	}
+	b.toc();
+	if ( !isStringArray( out ) ) {
+		b.fail( 'should return an array of strings' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
+
+bench( pkg+'::kind', function benchmark( b ) {
+	var values;
+	var out;
+	var i;
+
+	values = [
+		'floating_point',
+		'integer'
+	];
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		out = dtypeChars( values[ i%values.length ] );
+		if ( out.length === 0 ) {
+			b.fail( 'should return a non-empty array' );
+		}
+	}
+	b.toc();
+	if ( !isStringArray( out ) ) {
+		b.fail( 'should return an array of strings' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});
+
+bench( pkg+'::kind,generic', function benchmark( b ) {
+	var values;
+	var out;
+	var i;
+
+	values = [
+		'floating_point_and_generic',
+		'integer_and_generic',
+		'boolean_and_generic'
+	];
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		out = dtypeChars( values[ i%values.length ] );
+		if ( out.length === 0 ) {
+			b.fail( 'should return a non-empty array' );
+		}
+	}
+	b.toc();
+	if ( !isStringArray( out ) ) {
+		b.fail( 'should return an array of strings' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});

lib/node_modules/@stdlib/ndarray/base/dtype-chars/docs/repl.txt

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+
+{{alias}}( [kind] )
+    Returns a list of ndarray data type single letter character abbreviations.
+
+    When not provided a data type "kind", the function returns a list of single
+    letter character abbreviations for all supported ndarray data types.
+
+    The function supports the following data type "kinds":
+
+    - floating_point: floating-point data types.
+    - real_floating_point: real-valued floating-point data types.
+    - complex_floating_point: complex-valued floating-point data types.
+    - boolean: boolean data types.
+    - integer: integer data types.
+    - signed_integer: signed integer data types.
+    - unsigned_integer: unsigned integer data types.
+    - real: real-valued data types.
+    - numeric: numeric data types.
+    - typed: typed data types.
+    - integer_index: integer index data types.
+    - boolean_index: boolean index data types.
+    - mask_index: mask index data types.
+    - typed_index: typed index data types.
+    - index: index data types.
+    - all: all data types.
+
+    Additionally, the function supports extending the "kinds" listed above by
+    appending a '_and_generic' suffix to the kind name (e.g., real_and_generic).
+
+    Parameters
+    ----------
+    kind: string (optional)
+        Data type kind.
+
+    Returns
+    -------
+    out: Array<string>
+        List of ndarray data type single letter character abbreviations.
+
+    Examples
+    --------
+    > var out = {{alias}}()
+    [...]
+    > out = {{alias}}( 'floating_point' )
+    [...]
+    > out = {{alias}}( 'floating_point_and_generic' )
+    [...]
+
+    See Also
+    --------
+

lib/node_modules/@stdlib/ndarray/base/dtype-chars/docs/types/index.d.ts

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+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2025 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+// TypeScript Version: 4.1
+
+/// <reference types="@stdlib/types"/>
+
+import { DataTypeKind } from '@stdlib/types/ndarray';
+
+/**
+* Returns a list of ndarray data type single letter character abbreviations.
+*
+* @param kind - data type kind
+* @returns list of ndarray data type single letter character abbreviations
+*
+* @example
+* var list = dtypeChars();
+* // returns [...]
+*
+* @example
+* var list = dtypeChars( 'floating_point' );
+* // returns [...]
+*/
+declare function dtypeChars( kind?: DataTypeKind ): Array<string>;
+
+
+// EXPORTS //
+
+export = dtypeChars;

lib/node_modules/@stdlib/ndarray/base/dtype-chars/docs/types/test.ts

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+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2025 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+import dtypeChars = require( './index' );
+
+
+// TESTS //
+
+// The function returns an array of data type strings...
+{
+	dtypeChars(); // $ExpectType string[]
+	dtypeChars( 'floating_point' ); // $ExpectType string[]
+	dtypeChars( 'floating_point_and_generic' ); // $ExpectType string[]
+}
+
+// The compiler throws an error if the function is provided an unsupported number of arguments...
+{
+	dtypeChars( 'floating_point', 2 ); // $ExpectError
+}