feat: added ndarray implementation for @stats/base/dvarmpn

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Author: DhruvArvindSingh

lib/node_modules/@stdlib/stats/base/dvarmpn/include/stdlib/stats/base/dvarmpn.h

@@ -19,7 +19,7 @@
 #ifndef STDLIB_STATS_BASE_DVARMPN_H
 #define STDLIB_STATS_BASE_DVARMPN_H
 
-#include <stdint.h>
+#include "stdlib/blas/base/shared.h"
 
 /*
 * If C++, prevent name mangling so that the compiler emits a binary file having undecorated names, thus mirroring the behavior of a C compiler.
@@ -31,7 +31,11 @@ extern "C" {
 /**
 * Computes the variance of a double-precision floating-point strided array provided a known mean and using Neely's correction algorithm.
 */
-double stdlib_strided_dvarmpn( const int64_t N, const double mean, const double correction, const double *X, const int64_t stride );
+double API_SUFFIX( stdlib_strided_dvarmpn )( const CBLAS_INT N, const double mean, const double correction, const double *X, const CBLAS_INT strideX );
+/**
+* Computes the variance of a double-precision floating-point strided array provided a known mean and using Neely's correction algorithm using alternative indexing semantics.
+*/
+double API_SUFFIX( stdlib_strided_dvarmpn_ndarray )( const CBLAS_INT N, const double mean, const double correction, const double *X, const CBLAS_INT strideX, const CBLAS_INT offsetX );
 
 #ifdef __cplusplus
 }

lib/node_modules/@stdlib/stats/base/dvarmpn/lib/dvarmpn.js

@@ -18,6 +18,12 @@
 
 'use strict';
 
+// MODULES //
+
+var stride2offset = require( '@stdlib/strided/base/stride2offset' );
+var ndarray = require( './ndarray.js' );
+
+
 // MAIN //
 
 /**
@@ -32,7 +38,7 @@
 * @param {number} mean - mean
 * @param {number} correction - degrees of freedom adjustment
 * @param {Float64Array} x - input array
-* @param {integer} stride - stride length
+* @param {integer} strideX - strideX length
 * @returns {number} variance
 *
 * @example
@@ -43,35 +49,9 @@
 * var v = dvarmpn( x.length, 1.0/3.0, 1, x, 1 );
 * // returns ~4.3333
 */
-function dvarmpn( N, mean, correction, x, stride ) {
-	var ix;
-	var M2;
-	var M;
-	var d;
-	var n;
-	var i;
-
-	n = N - correction;
-	if ( N <= 0 || n <= 0.0 ) {
-		return NaN;
-	}
-	if ( N === 1 || stride === 0 ) {
-		return 0.0;
-	}
-	if ( stride < 0 ) {
-		ix = (1-N) * stride;
-	} else {
-		ix = 0;
-	}
-	M2 = 0.0;
-	M = 0.0;
-	for ( i = 0; i < N; i++ ) {
-		d = x[ ix ] - mean;
-		M2 += d * d;
-		M += d;
-		ix += stride;
-	}
-	return (M2/n) - ((M/N)*(M/n));
+function dvarmpn( N, mean, correction, x, strideX ) {
+	var ox = stride2offset( N, strideX);
+	return ndarray( N, mean, correction, x, strideX, ox );
 }
 
 

lib/node_modules/@stdlib/stats/base/dvarmpn/lib/dvarmpn.native.js

@@ -32,7 +32,7 @@ var addon = require( './../src/addon.node' );
 * @param {number} mean - mean
 * @param {number} correction - degrees of freedom adjustment
 * @param {Float64Array} x - input array
-* @param {integer} stride - stride length
+* @param {integer} strideX - strideX length
 * @returns {number} variance
 *
 * @example
@@ -43,8 +43,8 @@ var addon = require( './../src/addon.node' );
 * var v = dvarmpn( x.length, 1.0/3.0, 1, x, 1 );
 * // returns ~4.3333
 */
-function dvarmpn( N, mean, correction, x, stride ) {
-	return addon( N, mean, correction, x, stride );
+function dvarmpn( N, mean, correction, x, strideX ) {
+	return addon( N, mean, correction, x, strideX );
 }
 
 

lib/node_modules/@stdlib/stats/base/dvarmpn/lib/ndarray.js

@@ -32,21 +32,19 @@
 * @param {number} mean - mean
 * @param {number} correction - degrees of freedom adjustment
 * @param {Float64Array} x - input array
-* @param {integer} stride - stride length
-* @param {NonNegativeInteger} offset - starting index
+* @param {integer} strideX - strideX length
+* @param {NonNegativeInteger} offsetX - starting index
 * @returns {number} variance
 *
 * @example
 * var Float64Array = require( '@stdlib/array/float64' );
-* var floor = require( '@stdlib/math/base/special/floor' );
 *
 * var x = new Float64Array( [ 2.0, 1.0, 2.0, -2.0, -2.0, 2.0, 3.0, 4.0 ] );
-* var N = floor( x.length / 2 );
 *
-* var v = dvarmpn( N, 1.25, 1, x, 2, 1 );
+* var v = dvarmpn( 4, 1.25, 1, x, 2, 1 );
 * // returns 6.25
 */
-function dvarmpn( N, mean, correction, x, stride, offset ) {
+function dvarmpn( N, mean, correction, x, strideX, offsetX ) {
 	var ix;
 	var M2;
 	var M;
@@ -58,17 +56,17 @@ function dvarmpn( N, mean, correction, x, stride, offset ) {
 	if ( N <= 0 || n <= 0.0 ) {
 		return NaN;
 	}
-	if ( N === 1 || stride === 0 ) {
+	if ( N === 1 || strideX === 0 ) {
 		return 0.0;
 	}
-	ix = offset;
+	ix = offsetX;
 	M2 = 0.0;
 	M = 0.0;
 	for ( i = 0; i < N; i++ ) {
 		d = x[ ix ] - mean;
 		M2 += d * d;
 		M += d;
-		ix += stride;
+		ix += strideX;
 	}
 	return (M2/n) - ((M/N)*(M/n));
 }

lib/node_modules/@stdlib/stats/base/dvarmpn/lib/ndarray.native.js

@@ -20,8 +20,7 @@
 
 // MODULES //
 
-var Float64Array = require( '@stdlib/array/float64' );
-var addon = require( './dvarmpn.native.js' );
+var addon = require( './../src/addon.node' );
 
 
 // MAIN //
@@ -33,27 +32,20 @@ var addon = require( './dvarmpn.native.js' );
 * @param {number} mean - mean
 * @param {number} correction - degrees of freedom adjustment
 * @param {Float64Array} x - input array
-* @param {integer} stride - stride length
-* @param {NonNegativeInteger} offset - starting index
+* @param {integer} strideX - strideX length
+* @param {NonNegativeInteger} offsetX - starting index
 * @returns {number} variance
 *
 * @example
 * var Float64Array = require( '@stdlib/array/float64' );
-* var floor = require( '@stdlib/math/base/special/floor' );
 *
 * var x = new Float64Array( [ 2.0, 1.0, 2.0, -2.0, -2.0, 2.0, 3.0, 4.0 ] );
-* var N = floor( x.length / 2 );
 *
-* var v = dvarmpn( N, 1.25, 1, x, 2, 1 );
+* var v = dvarmpn( 4, 1.25, 1, x, 2, 1 );
 * // returns 6.25
 */
-function dvarmpn( N, mean, correction, x, stride, offset ) {
-	var view;
-	if ( stride < 0 ) {
-		offset += (N-1) * stride;
-	}
-	view = new Float64Array( x.buffer, x.byteOffset+(x.BYTES_PER_ELEMENT*offset), x.length-offset ); // eslint-disable-line max-len
-	return addon( N, mean, correction, view, stride );
+function dvarmpn( N, mean, correction, x, strideX, offsetX ) {
+	return addon.ndarray( N, mean, correction, x, strideX, offsetX );
 }
 
 

lib/node_modules/@stdlib/stats/base/dvarmpn/manifest.json

@@ -1,6 +1,7 @@
 {
   "options": {
-    "task": "build"
+    "task": "build",
+    "wasm": false
   },
   "fields": [
     {
@@ -27,8 +28,9 @@
   "confs": [
     {
       "task": "build",
+      "wasm": false,
       "src": [
-        "./src/dvarmpn.c"
+        "./src/main.c"
       ],
       "include": [
         "./include"
@@ -38,6 +40,8 @@
       ],
       "libpath": [],
       "dependencies": [
+        "@stdlib/blas/base/shared",
+        "@stdlib/strided/base/stride2offset",
         "@stdlib/napi/export",
         "@stdlib/napi/argv",
         "@stdlib/napi/argv-int64",
@@ -48,8 +52,9 @@
     },
     {
       "task": "benchmark",
+      "wasm": false,
       "src": [
-        "./src/dvarmpn.c"
+        "./src/main.c"
       ],
       "include": [
         "./include"
@@ -58,12 +63,16 @@
         "-lm"
       ],
       "libpath": [],
-      "dependencies": []
+      "dependencies": [
+        "@stdlib/blas/base/shared",
+        "@stdlib/strided/base/stride2offset"
+      ]
     },
     {
       "task": "examples",
+      "wasm": false,
       "src": [
-        "./src/dvarmpn.c"
+        "./src/main.c"
       ],
       "include": [
         "./include"
@@ -72,7 +81,26 @@
         "-lm"
       ],
       "libpath": [],
-      "dependencies": []
+      "dependencies": [
+        "@stdlib/blas/base/shared",
+        "@stdlib/strided/base/stride2offset"
+      ]
+    },
+    {
+      "task": "",
+      "wasm": true,
+      "src": [
+        "./src/main.c"
+      ],
+      "include": [
+        "./include"
+      ],
+      "libraries": [],
+      "libpath": [],
+      "dependencies": [
+        "@stdlib/blas/base/shared",
+        "@stdlib/strided/base/stride2offset"
+      ]
     }
   ]
 }

lib/node_modules/@stdlib/stats/base/dvarmpn/src/addon.c

@@ -35,12 +35,31 @@
 static napi_value addon( napi_env env, napi_callback_info info ) {
 	STDLIB_NAPI_ARGV( env, info, argv, argc, 5 );
 	STDLIB_NAPI_ARGV_INT64( env, N, argv, 0 );
-	STDLIB_NAPI_ARGV_INT64( env, stride, argv, 4 );
+	STDLIB_NAPI_ARGV_INT64( env, strideX, argv, 4 );
 	STDLIB_NAPI_ARGV_DOUBLE( env, mean, argv, 1 );
 	STDLIB_NAPI_ARGV_DOUBLE( env, correction, argv, 2 );
-	STDLIB_NAPI_ARGV_STRIDED_FLOAT64ARRAY( env, X, N, stride, argv, 3 );
-	STDLIB_NAPI_CREATE_DOUBLE( env, stdlib_strided_dvarmpn( N, mean, correction, X, stride ), v );
+	STDLIB_NAPI_ARGV_STRIDED_FLOAT64ARRAY( env, X, N, strideX, argv, 3 );
+	STDLIB_NAPI_CREATE_DOUBLE( env, stdlib_strided_dvarmpn( N, mean, correction, X, strideX ), v );
 	return v;
 }
 
-STDLIB_NAPI_MODULE_EXPORT_FCN( addon )
+/**
+* Receives JavaScript callback invocation data.
+*
+* @param env    environment under which the function is invoked
+* @param info   callback data
+* @return       Node-API value
+*/
+static napi_value addon_method( napi_env env, napi_callback_info info ) {
+	STDLIB_NAPI_ARGV( env, info, argv, argc, 6 );
+	STDLIB_NAPI_ARGV_INT64( env, N, argv, 0 );
+	STDLIB_NAPI_ARGV_INT64( env, strideX, argv, 4 );
+	STDLIB_NAPI_ARGV_INT64( env, offsetX, argv, 5 );
+	STDLIB_NAPI_ARGV_DOUBLE( env, mean, argv, 1 );
+	STDLIB_NAPI_ARGV_DOUBLE( env, correction, argv, 2 );
+	STDLIB_NAPI_ARGV_STRIDED_FLOAT64ARRAY( env, X, N, strideX, argv, 3 );
+	STDLIB_NAPI_CREATE_DOUBLE( env, stdlib_strided_dvarmpn_ndarray( N, mean, correction, X, strideX, offsetX ), v );
+	return v;
+}
+
+STDLIB_NAPI_MODULE_EXPORT_FCN_WITH_METHOD( addon, "ndarray", addon_method )

…@stdlib/stats/base/dvarmpn/src/dvarmpn.c …es/@stdlib/stats/base/dvarmpn/src/main.clib/node_modules/@stdlib/stats/base/dvarmpn/src/dvarmpn.c renamed to lib/node_modules/@stdlib/stats/base/dvarmpn/src/main.c lib/node_modules/@stdlib/stats/base/dvarmpn/src/dvarmpn.c renamed to lib/node_modules/@stdlib/stats/base/dvarmpn/src/main.c

@@ -17,7 +17,8 @@
 */
 
 #include "stdlib/stats/base/dvarmpn.h"
-#include <stdint.h>
+#include "stdlib/strided/base/stride2offset.h"
+#include "stdlib/blas/base/shared.h"
 
 /**
 * Computes the variance of a double-precision floating-point strided array provided a known mean and using Neely's correction algorithm.
@@ -31,12 +32,34 @@
 * @param mean        mean
 * @param correction  degrees of freedom adjustment
 * @param X           input array
-* @param stride      stride length
+* @param strideX      strideX length
 * @return            output value
 */
-double stdlib_strided_dvarmpn( const int64_t N, const double mean, const double correction, const double *X, const int64_t stride ) {
-	int64_t ix;
-	int64_t i;
+double API_SUFFIX( stdlib_strided_dvarmpn )( const CBLAS_INT N, const double mean, const double correction, const double *X, const CBLAS_INT strideX ) {
+	const CBLAS_INT ox = stdlib_strided_stride2offset( N, strideX );
+	return API_SUFFIX(stdlib_strided_dvarmpn_ndarray)( N, mean, correction, X, strideX, ox );
+}
+
+/**
+* Computes the variance of a double-precision floating-point strided array provided a known mean and using Neely's correction algorithm.
+*
+* ## References
+*
+* -   Neely, Peter M. 1966. "Comparison of Several Algorithms for Computation of Means, Standard Deviations and Correlation Coefficients." _Communications of the ACM_ 9 (7). Association for Computing Machinery: 496–99. doi:[10.1145/365719.365958](https://doi.org/10.1145/365719.365958).
+* -   Schubert, Erich, and Michael Gertz. 2018. "Numerically Stable Parallel Computation of (Co-)Variance." In _Proceedings of the 30th International Conference on Scientific and Statistical Database Management_. New York, NY, USA: Association for Computing Machinery. doi:[10.1145/3221269.3223036](https://doi.org/10.1145/3221269.3223036).
+*
+* @param N           number of indexed elements
+* @param mean        mean
+* @param correction  degrees of freedom adjustment
+* @param X           input array
+* @param strideX      strideX length
+* @param offsetX      starting index
+* @return            output value
+*/
+
+double API_SUFFIX( stdlib_strided_dvarmpn_ndarray )( const CBLAS_INT N, const double mean, const double correction, const double *X, const CBLAS_INT strideX, const CBLAS_INT offsetX ) {
+	CBLAS_INT ix;
+	CBLAS_INT i;
 	double dN;
 	double M2;
 	double M;
@@ -48,21 +71,17 @@ double stdlib_strided_dvarmpn( const int64_t N, const double mean, const double
 	if ( N <= 0 || n <= 0.0 ) {
 		return 0.0 / 0.0; // NaN
 	}
-	if ( N == 1 || stride == 0 ) {
+	if ( N == 1 || strideX == 0 ) {
 		return 0.0;
 	}
-	if ( stride < 0 ) {
-		ix = (1-N) * stride;
-	} else {
-		ix = 0;
-	}
+	ix = offsetX;
 	M2 = 0.0;
 	M = 0.0;
 	for ( i = 0; i < N; i++ ) {
 		d = X[ ix ] - mean;
 		M2 += d * d;
 		M += d;
-		ix += stride;
+		ix += strideX;
 	}
 	return (M2/n) - ((M/dN)*(M/n));
 }