chore: update test to use ULP-based testing & move hyp2f1NegCEqualBC to its own file

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Author: officiallyanee

lib/node_modules/@stdlib/math/base/special/hyp2f1/lib/hyp2f1negcequalbc.js

@@ -0,0 +1,81 @@
+/**
+* @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.
+*
+*
+* ## Notice
+*
+* The original C code and copyright notice are from the [Cephes Mathematical Library]{@link https://www.netlib.org/cephes/}. The implementation has been modified for JavaScript.
+*
+* ```text
+* (C) Copyright Stephen L. Moshier 1984, 1987, 1992, 2000.
+*
+* Use, modification and distribution are subject to the
+* Cephes Mathematical Library License. (See accompanying file
+* LICENSE or copy at https://smath.com/en-US/view/CephesMathLibrary/license)
+* ```
+*/
+
+'use strict';
+
+// MODULES //
+
+var abs = require( '@stdlib/math/base/special/abs' );
+var max = require( '@stdlib/math/base/special/max' );
+
+
+// MAIN //
+
+/**
+* Evaluates 2F1(a, b; b; x) when `b = c` is a negative integer using AMS55 #15.4.2.
+*
+* @private
+* @param {number} a - first parameter
+* @param {number} b - second parameter (equals c, a non-positive integer)
+* @param {number} x - argument
+* @returns {number} function value, or NaN if precision is insufficient
+*/
+function hyp2f1NegCEqualBC( a, b, x ) {
+	var collectorMax;
+	var collector;
+	var sum;
+	var k;
+
+	collectorMax = 1.0;
+	collector = 1.0;
+	sum = 1.0;
+
+	if ( !( abs( b ) < 1.0e5 ) ) {
+		return NaN;
+	}
+
+	for ( k = 1; k <= -b; k++ ) {
+		collector *= ( a + k - 1.0 ) * x / k;
+		collectorMax = max( abs( collector ), collectorMax );
+		sum += collector;
+	}
+
+	if ( 1.0e-16 * ( 1.0 + ( collectorMax / abs( sum ) ) ) > 1.0e-7 ) {
+		return NaN;
+	}
+
+	return sum;
+}
+
+
+// EXPORTS //
+
+module.exports = hyp2f1NegCEqualBC;

lib/node_modules/@stdlib/math/base/special/hyp2f1/lib/main.js

@@ -39,8 +39,8 @@ var round = require( '@stdlib/math/base/special/round' );
 var gamma = require( '@stdlib/math/base/special/gamma' );
 var pow = require( '@stdlib/math/base/special/pow' );
 var abs = require( '@stdlib/math/base/special/abs' );
-var max = require( '@stdlib/math/base/special/max' );
 var isNonPositiveInteger = require( './isnonpositiveinteger.js' );
+var hyp2f1NegCEqualBC = require( './hyp2f1negcequalbc.js' );
 var isInteger = require( './isinteger.js' );
 var hys2f1 = require( './hys2f1.js' );
 var hyt2f1 = require( './hyt2f1.js' );
@@ -52,41 +52,6 @@ var config = require( './config.json' );
 var ETHRESH = config.ETHRESH;
 
 
-// FUNCTIONS //
-
-/**
-* Evaluates 2F1(a, b; b; x) when `b = c` is a negative integer using AMS55 #15.4.2.
-*
-* @private
-* @param {number} a - first parameter
-* @param {number} b - second parameter (equals c, a non-positive integer)
-* @param {number} x - argument
-* @returns {number} function value, or NaN if precision is insufficient
-*/
-function hyp2f1NegCEqualBC( a, b, x ) {
-	var collectorMax;
-	var collector;
-	var sum;
-	var k;
-
-	if ( !( abs( b ) < 1.0e5 ) ) {
-		return NaN;
-	}
-	collectorMax = 1.0;
-	collector = 1.0;
-	sum = 1.0;
-	for ( k = 1; k <= -b; k++ ) {
-		collector *= ( a + k - 1.0 ) * x / k;
-		collectorMax = max( abs( collector ), collectorMax );
-		sum += collector;
-	}
-	if ( 1.0e-16 * ( 1.0 + ( collectorMax / abs( sum ) ) ) > 1.0e-7 ) {
-		return NaN;
-	}
-	return sum;
-}
-
-
 // MAIN //
 
 /**

lib/node_modules/@stdlib/math/base/special/hyp2f1/test/test.js

@@ -257,17 +257,13 @@ tape( 'the function correctly evaluates the hypergeometric function', function t
 
 	for ( i = 0; i < x.length; i++ ) {
 		v = hyp2f1( a[ i ], b[ i ], c[ i ], x[ i ] );
-		delta = abs( v - expected[ i ] );
-		tol = 8.0 * EPS * abs( expected[ i ] );
-		t.ok( delta <= tol, 'within tolerance. a: ' + a[ i ] + ' b: ' + b[ i ] + ' c: ' + c[ i ] + ' x: ' + x[ i ] + '. Value: ' + v + '. Expected: ' + expected[ i ] + '. Delta: ' + delta + '. Tolerance: ' + tol + '.' );
+		t.strictEqual( isAlmostSameValue( v, expected[ i ], 12 ), true, 'returns expected value.' );
 	}
 	t.end();
 });
 
 tape( 'the function correctly evaluates the hypergeometric function', function test( t ) {
 	var expected;
-	var delta;
-	var tol;
 	var a;
 	var b;
 	var c;
@@ -283,17 +279,13 @@ tape( 'the function correctly evaluates the hypergeometric function', function t
 
 	for ( i = 0; i < x.length; i++ ) {
 		v = hyp2f1( a[ i ], b[ i ], c[ i ], x[ i ] );
-		delta = abs( v - expected[ i ] );
-		tol = EPS * abs( expected[ i ] );
-		t.ok( delta <= tol, 'within tolerance. a: ' + a[ i ] + ' b: ' + b[ i ] + ' c: ' + c[ i ] + ' x: ' + x[ i ] + '. Value: ' + v + '. Expected: ' + expected[ i ] + '. Delta: ' + delta + '. Tolerance: ' + tol + '.' );
+		t.strictEqual( isAlmostSameValue( v, expected[ i ], 1 ), true, 'returns expected value.' );
 	}
 	t.end();
 });
 
 tape( 'the function correctly evaluates the hypergeometric function', function test( t ) {
 	var expected;
-	var delta;
-	var tol;
 	var a;
 	var b;
 	var c;