Run results for: avgBy reduce vs map first

Run details:

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/135.0.0.0 Safari/537.36

Browser: Chrome 135

Operating system: Windows

Device Platform: Desktop

Date tested: one year ago

reduce

893K/s

map then reduce

141K/s

View exact numbers

Test name	Executions per second
✓ reduce	893,110 Ops/sec
map then reduce	140,538 Ops/sec

HTML Preparation code:

<script src="https://cdn.jsdelivr.net/lodash/4.16.0/lodash.min.js"></script>

Script Preparation code:

var data = [];
for (let i = 0; i < 1000; i++) {
    data.push({ value: Math.random() * 100 });
}

function getValue(obj) {
    return obj.value;
}

Tests:

reduce
data.reduce((sum, obj) => sum + getValue(obj), 0) / data.length;
map then reduce
data.map(getValue).reduce((sum, val) => sum + val, 0) / data.length;