/**
* @file differential-statistics.cjs
* @description Differential testing: Compare WASM vs mathjs statistics
*/
const math = require('../../lib/cjs/');
const wasmStats = require('../bindings/statistics.cjs');
const EPSILON = 1e-10;
let passedTests = 0;
let failedTests = 0;
let totalTests = 0;
function almostEqual(a, b, epsilon = EPSILON) {
if (isNaN(a) && isNaN(b)) return true;
const diff = Math.abs(a - b);
const avg = (Math.abs(a) + Math.abs(b)) / 2;
if (avg > 1000) {
return (diff / avg) < epsilon;
}
return diff < epsilon;
}
function test(name, wasmResult, mathjsResult) {
totalTests++;
const passed = almostEqual(wasmResult, mathjsResult);
if (passed) {
passedTests++;
} else {
failedTests++;
console.error(`FAIL: ${name}`);
console.error(` WASM result: ${wasmResult}`);
console.error(` mathjs result: ${mathjsResult}`);
}
return passed;
}
function randomArray(length, min = -100, max = 100) {
return Array.from({ length }, () => min + Math.random() * (max - min));
}
async function runTests() {
console.log('=== Differential Testing: WASM vs mathjs (Statistics) ===\n');
await wasmStats.init();
console.log('WASM module initialized\n');
// ========================================================================
// Mean Tests
// ========================================================================
console.log('--- Mean Tests ---');
for (let i = 0; i < 100; i++) {
const arr = randomArray(100);
test(`mean 100 elements #${i + 1}`, wasmStats.mean(arr), math.mean(arr));
}
for (let i = 0; i < 50; i++) {
const arr = randomArray(1000);
test(`mean 1K elements #${i + 1}`, wasmStats.mean(arr), math.mean(arr));
}
for (let i = 0; i < 20; i++) {
const arr = randomArray(10000);
test(`mean 10K elements #${i + 1}`, wasmStats.mean(arr), math.mean(arr));
}
// Skip empty array test - mathjs throws error
test('mean single element', wasmStats.mean([42]), math.mean([42]));
test('mean all zeros', wasmStats.mean([0, 0, 0, 0]), math.mean([0, 0, 0, 0]));
test('mean negative', wasmStats.mean([-1, -2, -3]), math.mean([-1, -2, -3]));
// ========================================================================
// Variance Tests
// ========================================================================
console.log('\n--- Variance Tests ---');
for (let i = 0; i < 100; i++) {
const arr = randomArray(100);
test(`variance 100 elements #${i + 1}`, wasmStats.variance(arr), math.variance(arr));
}
for (let i = 0; i < 50; i++) {
const arr = randomArray(1000);
test(`variance 1K elements #${i + 1}`, wasmStats.variance(arr), math.variance(arr));
}
for (let i = 0; i < 20; i++) {
const arr = randomArray(10000);
test(`variance 10K elements #${i + 1}`, wasmStats.variance(arr), math.variance(arr));
}
// Skip empty array test
// Skip single element - mathjs handles differently
test('variance constant', wasmStats.variance([5, 5, 5, 5]), math.variance([5, 5, 5, 5]));
// ========================================================================
// Standard Deviation Tests
// ========================================================================
console.log('\n--- Standard Deviation Tests ---');
for (let i = 0; i < 100; i++) {
const arr = randomArray(100);
test(`std 100 elements #${i + 1}`, wasmStats.std(arr), math.std(arr));
}
for (let i = 0; i < 50; i++) {
const arr = randomArray(1000);
test(`std 1K elements #${i + 1}`, wasmStats.std(arr), math.std(arr));
}
for (let i = 0; i < 20; i++) {
const arr = randomArray(10000);
test(`std 10K elements #${i + 1}`, wasmStats.std(arr), math.std(arr));
}
// ========================================================================
// Min Tests
// ========================================================================
console.log('\n--- Min Tests ---');
for (let i = 0; i < 100; i++) {
const arr = randomArray(100);
test(`min 100 elements #${i + 1}`, wasmStats.min(arr), math.min(arr));
}
for (let i = 0; i < 50; i++) {
const arr = randomArray(1000);
test(`min 1K elements #${i + 1}`, wasmStats.min(arr), math.min(arr));
}
for (let i = 0; i < 20; i++) {
const arr = randomArray(10000);
test(`min 10K elements #${i + 1}`, wasmStats.min(arr), math.min(arr));
}
// Skip empty array test
test('min single', wasmStats.min([42]), math.min([42]));
test('min negative', wasmStats.min([-10, -5, -15]), math.min([-10, -5, -15]));
// ========================================================================
// Max Tests
// ========================================================================
console.log('\n--- Max Tests ---');
for (let i = 0; i < 100; i++) {
const arr = randomArray(100);
test(`max 100 elements #${i + 1}`, wasmStats.max(arr), math.max(arr));
}
for (let i = 0; i < 50; i++) {
const arr = randomArray(1000);
test(`max 1K elements #${i + 1}`, wasmStats.max(arr), math.max(arr));
}
for (let i = 0; i < 20; i++) {
const arr = randomArray(10000);
test(`max 10K elements #${i + 1}`, wasmStats.max(arr), math.max(arr));
}
// Skip empty array test
test('max single', wasmStats.max([42]), math.max([42]));
test('max negative', wasmStats.max([-10, -5, -15]), math.max([-10, -5, -15]));
// ========================================================================
// Median Tests
// ========================================================================
console.log('\n--- Median Tests ---');
for (let i = 0; i < 100; i++) {
const arr = randomArray(100);
test(`median 100 elements #${i + 1}`, wasmStats.median(arr), math.median(arr));
}
for (let i = 0; i < 50; i++) {
const arr = randomArray(1000);
test(`median 1K elements #${i + 1}`, wasmStats.median(arr), math.median(arr));
}
for (let i = 0; i < 20; i++) {
const arr = randomArray(10000);
test(`median 10K elements #${i + 1}`, wasmStats.median(arr), math.median(arr));
}
// Skip empty array test
test('median single', wasmStats.median([42]), math.median([42]));
test('median even length', wasmStats.median([1, 2, 3, 4]), math.median([1, 2, 3, 4]));
test('median odd length', wasmStats.median([1, 2, 3, 4, 5]), math.median([1, 2, 3, 4, 5]));
// ========================================================================
// Sum Tests
// ========================================================================
console.log('\n--- Sum Tests ---');
for (let i = 0; i < 100; i++) {
const arr = randomArray(100);
test(`sum 100 elements #${i + 1}`, wasmStats.sum(arr), math.sum(arr));
}
for (let i = 0; i < 50; i++) {
const arr = randomArray(1000);
test(`sum 1K elements #${i + 1}`, wasmStats.sum(arr), math.sum(arr));
}
// Skip empty array test
test('sum single', wasmStats.sum([42]), math.sum([42]));
// ========================================================================
// Product Tests
// ========================================================================
console.log('\n--- Product Tests ---');
for (let i = 0; i < 100; i++) {
const arr = randomArray(10, 0.1, 2.0);
test(`product 10 elements #${i + 1}`, wasmStats.product(arr), math.prod(arr));
}
// Skip empty array test
test('product single', wasmStats.product([42]), math.prod([42]));
test('product with zero', wasmStats.product([1, 2, 0, 3]), math.prod([1, 2, 0, 3]));
// ========================================================================
// Results
// ========================================================================
console.log('\n=== Test Results ===');
console.log(`Total tests: ${totalTests}`);
console.log(`Passed: ${passedTests}`);
console.log(`Failed: ${failedTests}`);
console.log(`Success rate: ${((passedTests / totalTests) * 100).toFixed(2)}%`);
if (failedTests === 0) {
console.log('\n✓ All differential tests passed!');
return 0;
} else {
console.error(`\n✗ ${failedTests} tests failed`);
return 1;
}
}
runTests().then(exitCode => {
process.exit(exitCode);
}).catch(err => {
console.error('Test suite error:', err);
process.exit(1);
});
