eggheadio-projects/reduce-data-with-javascript: null

.DS_Store

# reduce-data-with-javascript

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>Plunker</title>
</head>
<body>
  <script>
    // Allows Plunker to display logs in preview panel 
    // for better in-browser experience
    var originalConsoleLog = console.log
    console.log = function () {
      originalConsoleLog.apply(console, arguments)
      var args = Array.prototype.slice.call(arguments);
      document.body.innerText += args.join(' ') + '\n';
      document.body.style['fontFamily'] = 'monospace';
      document.body.style['fontSize'] = '1.5em';
    };
  </script>
	<script src="script.js"></script>
</body>
</html>

var data = [1, 2, 3];
var doubled = data.reduce(function(acc, value) {
  acc.push(value * 2);

  return acc;
}, []);

var doubleMapped = data.map(function(item) {
  return item * 2;
});

var data2 = [1, 2, 3, 4, 5, 6];
var evens = data2.reduce(function(acc, value) {
  if (value % 2 === 0) {
    acc.push(value);
  }

  return acc;
}, []);

var evenFiltered = data2.filter(function(item) {
  return (item % 2 === 0);
});

var filterMapped = data2.filter(function(value) {
  return value % 2 === 0;
}).map(function(value) {
  return value * 2;
});

var bigData = [];
for (var i = 0; i < 1000000; i++) {
  bigData[i] = i;
}


let filterBegin = Date.now()
var filterMappedBigData = bigData.filter(function(value) {
  return value % 2 === 0;
}).map(function(value) {
  return value * 2;
});
let filterEnd = Date.now()
let filtertimeSpent = (filterEnd-filterBegin)/1000 + "secs";


let reducedBegin=Date.now();
var reducedBigData = bigData.reduce(function(acc, value) {
  if (value % 2 === 0) {
    acc.push(value * 2);
  }
  return acc;
}, []);
let reducedEnd = Date.now();
let reducedtimeSpent = (reducedEnd-reducedBegin)/1000 + " secs";

console.log("filtered Big Data:", filtertimeSpent)
console.log("reduced Big Data:", reducedtimeSpent)