feat: add support for accessor arrays and refactor stats/base/max-by

PR-URL: #7129
Co-authored-by: Athan Reines <kgryte@gmail.com>
Reviewed-by: Athan Reines <kgryte@gmail.com>

Author: gururaj1512

lib/node_modules/@stdlib/stats/base/max-by/README.md

@@ -30,9 +30,9 @@ limitations under the License.
 var maxBy = require( '@stdlib/stats/base/max-by' );
 ```
 
-#### maxBy( N, x, stride, clbk\[, thisArg] )
+#### maxBy( N, x, strideX, clbk\[, thisArg] )
 
-Calculates the maximum value of strided array `x` via a callback function.
+Computes the maximum value of a strided array via a callback function.
 
 ```javascript
 function accessor( v ) {
@@ -49,7 +49,7 @@ The function has the following parameters:
 
 -   **N**: number of indexed elements.
 -   **x**: input [`Array`][mdn-array], [`typed array`][mdn-typed-array], or an array-like object (excluding strings and functions).
--   **stride**: index increment.
+-   **strideX**: stride length for `x`.
 -   **clbk**: callback function.
 -   **thisArg**: execution context (_optional_).
 
@@ -81,27 +81,23 @@ var cnt = context.count;
 // returns 8
 ```
 
-The `N` and `stride` parameters determine which elements in `x` are accessed at runtime. For example, to access every other element
+The `N` and stride parameters determine which elements in the strided array are accessed at runtime. For example, to access every other element
 
 ```javascript
-var floor = require( '@stdlib/math/base/special/floor' );
-
 function accessor( v ) {
     return v * 2.0;
 }
 
 var x = [ -2.0, 1.0, 3.0, -5.0, 4.0, 0.0, -1.0, -3.0 ];
-var N = floor( x.length / 2 );
 
-var v = maxBy( N, x, 2, accessor );
+var v = maxBy( 4, x, 2, accessor );
 // returns 8.0
 ```
 
 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' );
-var floor = require( '@stdlib/math/base/special/floor' );
 
 function accessor( v ) {
     return v * 2.0;
@@ -112,16 +108,15 @@ 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
-var N = floor( x0.length/2 );
 
 // Access every other element...
-var v = maxBy( N, x1, 2, accessor );
+var v = maxBy( 3, x1, 2, accessor );
 // returns -4.0
 ```
 
-#### maxBy.ndarray( N, x, stride, offset, clbk\[, thisArg] )
+#### maxBy.ndarray( N, x, strideX, offsetX, clbk\[, thisArg] )
 
-Calculates the maximum value of strided array `x` via a callback function and using alternative indexing semantics.
+Computes the maximum value of a strided array via a callback function and using alternative indexing semantics.
 
 ```javascript
 function accessor( v ) {
@@ -136,9 +131,9 @@ var v = maxBy.ndarray( x.length, x, 1, 0, accessor );
 
 The function has the following additional parameters:
 
--   **offset**: starting index.
+-   **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 `x`
+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 `x`
 
 ```javascript
 function accessor( v ) {
@@ -162,6 +157,7 @@ var v = maxBy.ndarray( 3, x, 1, x.length-3, accessor );
 -   If `N <= 0`, both functions return `NaN`.
 -   A provided callback function should return a numeric value.
 -   If a provided callback function does not return any value (or equivalently, explicitly returns `undefined`), the value is **ignored**.
+-   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]).
 -   When possible, prefer using [`dmax`][@stdlib/stats/strided/dmax], [`smax`][@stdlib/stats/strided/smax], and/or [`max`][@stdlib/stats/base/max], as, depending on the environment, these interfaces are likely to be significantly more performant.
 
 </section>
@@ -175,15 +171,16 @@ var v = maxBy.ndarray( 3, x, 1, x.length-3, accessor );
 <!-- eslint no-undef: "error" -->
 
 ```javascript
-var discreteUniform = require( '@stdlib/random/base/discrete-uniform' ).factory;
-var filledarrayBy = require( '@stdlib/array/filled-by' );
+var discreteUniform = require( '@stdlib/random/array/discrete-uniform' );
 var maxBy = require( '@stdlib/stats/base/max-by' );
 
 function accessor( v ) {
     return v * 2.0;
 }
 
-var x = filledarrayBy( 10, 'float64', discreteUniform( -50, 50 ) );
+var x = discreteUniform( 10, -50, 50, {
+    'dtype': 'float64'
+});
 console.log( x );
 
 var v = maxBy( x.length, x, 1, accessor );
@@ -220,6 +217,8 @@ console.log( v );
 
 [mdn-typed-array]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray
 
+[@stdlib/array/base/accessor]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/array/base/accessor
+
 <!-- <related-links> -->
 
 [@stdlib/stats/strided/dmax]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/stats/strided/dmax

lib/node_modules/@stdlib/stats/base/max-by/benchmark/benchmark.js

@@ -21,11 +21,18 @@
 // MODULES //
 
 var bench = require( '@stdlib/bench' );
-var randu = require( '@stdlib/random/base/randu' );
+var uniform = require( '@stdlib/random/array/uniform' );
 var isnan = require( '@stdlib/math/base/assert/is-nan' );
 var pow = require( '@stdlib/math/base/special/pow' );
 var pkg = require( './../package.json' ).name;
-var maxBy = require( './../lib/max_by.js' );
+var maxBy = require( './../lib/main.js' );
+
+
+// VARIABLES //
+
+var options = {
+	'dtype': 'generic'
+};
 
 
 // FUNCTIONS //
@@ -49,13 +56,7 @@ function accessor( value ) {
 * @returns {Function} benchmark function
 */
 function createBenchmark( len ) {
-	var x;
-	var i;
-
-	x = [];
-	for ( i = 0; i < len; i++ ) {
-		x.push( ( randu()*20.0 ) - 10.0 );
-	}
+	var x = uniform( len, -10, 10, options );
 	return benchmark;
 
 	function benchmark( b ) {

lib/node_modules/@stdlib/stats/base/max-by/benchmark/benchmark.ndarray.js

@@ -21,13 +21,20 @@
 // MODULES //
 
 var bench = require( '@stdlib/bench' );
-var randu = require( '@stdlib/random/base/randu' );
+var uniform = require( '@stdlib/random/array/uniform' );
 var isnan = require( '@stdlib/math/base/assert/is-nan' );
 var pow = require( '@stdlib/math/base/special/pow' );
 var pkg = require( './../package.json' ).name;
 var maxBy = require( './../lib/ndarray.js' );
 
 
+// VARIABLES //
+
+var options = {
+	'dtype': 'generic'
+};
+
+
 // FUNCTIONS //
 
 /**
@@ -49,13 +56,7 @@ function accessor( value ) {
 * @returns {Function} benchmark function
 */
 function createBenchmark( len ) {
-	var x;
-	var i;
-
-	x = [];
-	for ( i = 0; i < len; i++ ) {
-		x.push( ( randu()*20.0 ) - 10.0 );
-	}
+	var x = uniform( len, -10, 10, options );
 	return benchmark;
 
 	function benchmark( b ) {

lib/node_modules/@stdlib/stats/base/max-by/docs/repl.txt

@@ -1,9 +1,9 @@
 
-{{alias}}( N, x, stride, clbk[, thisArg] )
-    Calculates the maximum value of a strided array via a callback function.
+{{alias}}( N, x, strideX, clbk[, thisArg] )
+    Computes the maximum value of a strided array via a callback function.
 
-    The `N` and `stride` parameters determine which elements in `x` are accessed
-    at runtime.
+    The `N` and stride parameters determine which elements in the strided array
+    are accessed at runtime.
 
     Indexing is relative to the first index. To introduce an offset, use typed
     array views.
@@ -31,8 +31,8 @@
         Input array/collection. If provided an object, the object must be array-
         like (excluding strings and functions).
 
-    stride: integer
-        Index increment for `x`.
+    strideX: integer
+        Stride length.
 
     clbk: Function
         Callback function.
@@ -53,25 +53,24 @@
     > {{alias}}( x.length, x, 1, accessor )
     8.0
 
-    // Using `N` and `stride` parameters:
+    // Using `N` and stride parameters:
     > x = [ -2.0, 1.0, 3.0, -5.0, 4.0, -1.0, -3.0 ];
-    > var N = {{alias:@stdlib/math/base/special/floor}}( x.length / 2 );
-    > {{alias}}( N, x, 2, accessor )
+    > {{alias}}( 3, x, 2, accessor )
     8.0
 
     // Using view offsets:
     > var x0 = new {{alias:@stdlib/array/float64}}( [ 1.0, -2.0, 3.0, -4.0, 5.0, -6.0 ] );
     > var x1 = new {{alias:@stdlib/array/float64}}( x0.buffer, x0.BYTES_PER_ELEMENT*1 );
-    > N = {{alias:@stdlib/math/base/special/floor}}( x0.length / 2 );
-    > {{alias}}( N, x1, 2, accessor )
+    > {{alias}}( 3, x1, 2, accessor )
     -4.0
 
-{{alias}}.ndarray( N, x, stride, offset, clbk[, thisArg] )
+
+{{alias}}.ndarray( N, x, strideX, offsetX, clbk[, thisArg] )
     Calculates the maximum value of a strided array via a callback function and
     using alternative indexing semantics.
 
     While typed array views mandate a view offset based on the underlying
-    buffer, the `offset` parameter supports indexing semantics based on a
+    buffer, the offset parameter supports indexing semantics based on a
     starting index.
 
     Parameters
@@ -83,11 +82,11 @@
         Input array/collection. If provided an object, the object must be array-
         like (excluding strings and functions).
 
-    stride: integer
-        Index increment for `x`.
+    strideX: integer
+        Stride length.
 
-    offset: integer
-        Starting index of `x`.
+    offsetX: integer
+        Starting index.
 
     clbk: Function
         Callback function.
@@ -110,8 +109,7 @@
 
     // Using an index offset:
     > x = [ 1.0, -2.0, 3.0, -4.0, 5.0, -6.0 ];
-    > var N = {{alias:@stdlib/math/base/special/floor}}( x.length / 2 );
-    > {{alias}}.ndarray( N, x, 2, 1, accessor )
+    > {{alias}}.ndarray( 3, x, 2, 1, accessor )
     -4.0
 
     See Also

lib/node_modules/@stdlib/stats/base/max-by/docs/types/index.d.ts

@@ -20,7 +20,12 @@
 
 /// <reference types="@stdlib/types"/>
 
-import { Collection } from '@stdlib/types/array';
+import { NumericArray, Collection, AccessorArrayLike } from '@stdlib/types/array';
+
+/**
+* Input array.
+*/
+type InputArray = NumericArray | Collection<number> | AccessorArrayLike<number>;
 
 /**
 * Returns an accessed value.
@@ -83,7 +88,7 @@ type Callback<T, U> = Nullary<U> | Unary<T, U> | Binary<T, U> | Ternary<T, U> |
 */
 interface Routine {
 	/**
-	* Calculates the maximum value of a strided array via a callback function.
+	* Computes the maximum value of a strided array via a callback function.
 	*
 	* ## Notes
 	*
@@ -98,7 +103,7 @@ interface Routine {
 	*
 	* @param N - number of indexed elements
 	* @param x - input array
-	* @param stride - stride length
+	* @param strideX - stride length
 	* @param clbk - callback
 	* @param thisArg - execution context
 	* @returns maximum value
@@ -113,10 +118,10 @@ interface Routine {
 	* var v = maxBy( x.length, x, 1, accessor );
 	* // returns 8.0
 	*/
-	<T = unknown, U = unknown>( N: number, x: Collection<T>, stride: number, clbk: Callback<T, U>, thisArg?: ThisParameterType<Callback<T, U>> ): number;
+	<T = unknown, U = unknown>( N: number, x: InputArray, strideX: number, clbk: Callback<T, U>, thisArg?: ThisParameterType<Callback<T, U>> ): number;
 
 	/**
-	* Calculates the maximum value of a strided array via a callback function and using alternative indexing semantics.
+	* Computes the maximum value of a strided array via a callback function and using alternative indexing semantics.
 	*
 	* ## Notes
 	*
@@ -131,8 +136,8 @@ interface Routine {
 	*
 	* @param N - number of indexed elements
 	* @param x - input array
-	* @param stride - stride length
-	* @param offset - starting index
+	* @param strideX - stride length
+	* @param offsetX - starting index
 	* @param clbk - callback
 	* @param thisArg - execution context
 	* @returns maximum value
@@ -147,11 +152,11 @@ interface Routine {
 	* var v = maxBy.ndarray( x.length, x, 1, 0, accessor );
 	* // returns 8.0
 	*/
-	ndarray<T = unknown, U = unknown>( N: number, x: Collection<T>, stride: number, offset: number, clbk: Callback<T, U>, thisArg?: ThisParameterType<Callback<T, U>> ): number;
+	ndarray<T = unknown, U = unknown>( N: number, x: InputArray, strideX: number, offsetX: number, clbk: Callback<T, U>, thisArg?: ThisParameterType<Callback<T, U>> ): number;
 }
 
 /**
-* Calculates the maximum value of a strided array via a callback function.
+* Computes the maximum value of a strided array via a callback function
 *
 * ## Notes
 *
@@ -166,7 +171,7 @@ interface Routine {
 *
 * @param N - number of indexed elements
 * @param x - input array
-* @param stride - stride length
+* @param strideX - stride length
 * @param clbk - callback
 * @param thisArg - execution context
 * @returns maximum value

lib/node_modules/@stdlib/stats/base/max-by/docs/types/test.ts

@@ -16,6 +16,7 @@
 * limitations under the License.
 */
 
+import AccessorArray = require( '@stdlib/array/base/accessor' );
 import maxBy = require( './index' );
 
 const accessor = (): number => {
@@ -30,7 +31,10 @@ const accessor = (): number => {
 	const x = new Float64Array( 10 );
 
 	maxBy( x.length, x, 1, accessor ); // $ExpectType number
+	maxBy( x.length, new AccessorArray( x ), 1, accessor ); // $ExpectType number
+
 	maxBy( x.length, x, 1, accessor, {} ); // $ExpectType number
+	maxBy( x.length, new AccessorArray( x ), 1, accessor, {} ); // $ExpectType number
 }
 
 // The compiler throws an error if the function is provided a first argument which is not a number...
@@ -70,7 +74,7 @@ const accessor = (): number => {
 	maxBy( x.length, x, undefined, accessor ); // $ExpectError
 	maxBy( x.length, x, [], accessor ); // $ExpectError
 	maxBy( x.length, x, {}, accessor ); // $ExpectError
-	maxBy( x.length, x, ( x: number, accessor ): number => x, accessor ); // $ExpectError
+	maxBy( x.length, x, ( x: number ): number => x, accessor ); // $ExpectError
 }
 
 // The compiler throws an error if the function is provided a fourth argument which is not a function...
@@ -102,7 +106,10 @@ const accessor = (): number => {
 	const x = new Float64Array( 10 );
 
 	maxBy.ndarray( x.length, x, 1, 0, accessor ); // $ExpectType number
+	maxBy.ndarray( x.length, new AccessorArray( x ), 1, 0, accessor ); // $ExpectType number
+
 	maxBy.ndarray( x.length, x, 1, 0, accessor, {} ); // $ExpectType number
+	maxBy.ndarray( x.length, new AccessorArray( x ), 1, 0, accessor, {} ); // $ExpectType number
 }
 
 // The compiler throws an error if the `ndarray` method is provided a first argument which is not a number...