feat: add ndarray/base/scalar-dtype

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

@@ -0,0 +1,138 @@
+<!--
+
+@license Apache-2.0
+
+Copyright (c) 2026 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.
+
+-->
+
+# Scalar Data Type
+
+> Determine the default ndarray [data type][@stdlib/ndarray/dtypes] for a provided scalar value.
+
+<!-- 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 scalarDataType = require( '@stdlib/ndarray/base/scalar-dtype' );
+```
+
+#### scalarDataType( value )
+
+Returns the default ndarray [data type][@stdlib/ndarray/dtypes] for a provided scalar value.
+
+```javascript
+var dt = scalarDataType( 3.0 );
+// returns 'float64'
+
+dt = scalarDataType( true );
+// returns 'bool'
+
+dt = scalarDataType( null );
+// returns 'generic'
+```
+
+</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
+
+-   The function resolves data types as follows:
+
+    -   **number**: the default real-valued floating-point data type.
+    -   **boolean**: the default boolean data type.
+    -   **complex number**: a corresponding complex number data type, falling back to the default complex-valued floating-point data type when a provided complex-like object has an unrecognized data type.
+    -   **everything else**: `'generic'`.
+
+-   Only primitive numbers and booleans are recognized. A `Number` or `Boolean` object resolves to `'generic'`.
+
+</section>
+
+<!-- /.notes -->
+
+<!-- Package usage examples. -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+```javascript
+var Complex128 = require( '@stdlib/complex/float64/ctor' );
+var scalarDataType = require( '@stdlib/ndarray/base/scalar-dtype' );
+
+var values = [
+    3.14,
+    -1.0,
+    true,
+    false,
+    new Complex128( 1.0, 2.0 ),
+    'beep',
+    null,
+    [ 1, 2, 3 ]
+];
+
+var i;
+for ( i = 0; i < values.length; i++ ) {
+    console.log( '%s => %s', String( values[ i ] ), scalarDataType( values[ i ] ) );
+}
+```
+
+</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/scalar-dtype/benchmark/benchmark.js

@@ -0,0 +1,61 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 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 isString = require( '@stdlib/assert/is-string' ).isPrimitive;
+var Complex128 = require( '@stdlib/complex/float64/ctor' );
+var pkg = require( './../package.json' ).name;
+var scalarDataType = require( './../lib' );
+
+
+// MAIN //
+
+bench( pkg, function benchmark( b ) {
+	var values;
+	var out;
+	var i;
+
+	values = [
+		3.14,
+		-1.0,
+		true,
+		false,
+		new Complex128( 1.0, 2.0 ),
+		'beep',
+		null,
+		[ 1, 2, 3 ]
+	];
+
+	b.tic();
+	for ( i = 0; i < b.iterations; i++ ) {
+		out = scalarDataType( values[ i%values.length ] );
+		if ( typeof out !== 'string' ) {
+			b.fail( 'should return a string' );
+		}
+	}
+	b.toc();
+	if ( !isString( out ) ) {
+		b.fail( 'should return a string' );
+	}
+	b.pass( 'benchmark finished' );
+	b.end();
+});

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

@@ -0,0 +1,32 @@
+
+{{alias}}( value )
+    Returns the default ndarray data type for a provided scalar value.
+
+    If provided a number, the function returns the default real-valued
+    floating-point data type. If provided a boolean, the function returns the
+    default boolean data type. If provided a complex number, the function
+    returns a corresponding complex number data type. For all other values,
+    the function returns 'generic'.
+
+    Parameters
+    ----------
+    value: any
+        Scalar value.
+
+    Returns
+    -------
+    dt: string
+        ndarray data type.
+
+    Examples
+    --------
+    > var dt = {{alias}}( 3.0 )
+    'float64'
+    > dt = {{alias}}( true )
+    'bool'
+    > dt = {{alias}}( null )
+    'generic'
+
+    See Also
+    --------
+

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

@@ -0,0 +1,44 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 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 { DataType } from '@stdlib/types/ndarray';
+
+/**
+* Returns the default ndarray data type for a provided scalar value.
+*
+* @param value - scalar value
+* @returns ndarray data type
+*
+* @example
+* var dt = scalarDataType( 3.0 );
+* // returns 'float64'
+*
+* @example
+* var dt = scalarDataType( true );
+* // returns 'bool'
+*/
+declare function scalarDataType( value: any ): DataType;
+
+
+// EXPORTS //
+
+export = scalarDataType;

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

@@ -0,0 +1,35 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 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 scalarDataType = require( './index' );
+
+
+// TESTS //
+
+// The function returns a string...
+{
+	scalarDataType( 3.0 ); // $ExpectType DataType
+	scalarDataType( true ); // $ExpectType DataType
+	scalarDataType( null ); // $ExpectType DataType
+}
+
+// The compiler throws an error if the function is provided an unsupported number of arguments...
+{
+	scalarDataType(); // $ExpectError
+	scalarDataType( 3.0, 2.0 ); // $ExpectError
+}

lib/node_modules/@stdlib/ndarray/base/scalar-dtype/examples/index.js

@@ -0,0 +1,38 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 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';
+
+var Complex128 = require( '@stdlib/complex/float64/ctor' );
+var scalarDataType = require( './../lib' );
+
+var values = [
+	3.14,
+	-1.0,
+	true,
+	false,
+	new Complex128( 1.0, 2.0 ),
+	'beep',
+	null,
+	[ 1, 2, 3 ]
+];
+
+var i;
+for ( i = 0; i < values.length; i++ ) {
+	console.log( '%s => %s', String( values[ i ] ), scalarDataType( values[ i ] ) );
+}

lib/node_modules/@stdlib/ndarray/base/scalar-dtype/lib/index.js

@@ -0,0 +1,43 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 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';
+
+/**
+* Determine the default ndarray data type for a provided scalar value.
+*
+* @module @stdlib/ndarray/base/scalar-dtype
+*
+* @example
+* var scalarDataType = require( '@stdlib/ndarray/base/scalar-dtype' );
+*
+* var dt = scalarDataType( 3.0 );
+* // returns 'float64'
+*
+* dt = scalarDataType( true );
+* // returns 'bool'
+*/
+
+// MODULES //
+
+var scalarDataType = require( './main.js' );
+
+
+// EXPORTS //
+
+module.exports = scalarDataType;