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@2bam
Created May 7, 2023 10:02
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JS sorting algorithm benchmarks [keeping it in case it's lost]
//
// Thx https://www.measurethat.net/Benchmarks/Show/3549/0/javascript-sorting-algorithms
//
// 1000x random ordered: https://www.measurethat.net/Benchmarks/Show/3549/0/javascript-sorting-algorithms
// 1000x almost ordered: https://www.measurethat.net/Benchmarks/Show/25092/0/javascript-sorting-algorithms-best-case-almost-ordered
//
function swap(ary, a, b) {
var t = ary[a];
ary[a] = ary[b];
ary[b] = t;
}
// Built-in with comparison function (default sorting is "dictionary-style")
function builtin_sort(ary) {
return ary.sort(function(a, b) {
return a - b;
});
}
// Bubble Sort
function bubble_sort(ary) {
var a, b;
for (a = 0; a < ary.length; a++) {
for (b = a + 1; b < ary.length; b++) {
if (ary[a] > ary[b]) {
swap(ary, a, b);
}
}
}
return ary;
}
//Insertion sort
function insertion_sort(ary) {
for(var i=1,l=ary.length;i<l;i++) {
var value = ary[i];
for(var j=i - 1;j>=0;j--) {
if(ary[j] <= value)
break;
ary[j+1] = ary[j];
}
ary[j+1] = value;
}
return ary;
}
// Naive (but understandable) quicksort (memory hog)
function naive_quicksort(ary) {
if (ary.length <= 1) {
return ary;
}
var less = [],
greater = [],
pivot = ary.pop();
for (var i = 0; i < ary.length; i++) {
if (ary[i] < pivot) {
less.push(ary[i]);
} else {
greater.push(ary[i]);
}
}
less = naive_quicksort(less);
greater = naive_quicksort(greater);
return less.concat(pivot, greater);
}
// In place quicksort
function inplace_quicksort_partition(ary, start, end, pivotIndex) {
var i = start, j = end;
var pivot = ary[pivotIndex];
while(true) {
while(ary[i] < pivot) {i++};
j--;
while(pivot < ary[j]) {j--};
if(!(i<j)) {
return i;
}
swap(ary,i,j);
i++;
}
}
function inplace_quicksort(ary, start, end) {
if (start < end - 1) {
var pivotIndex = Math.round((start + end) / 2);
pivotIndex = inplace_quicksort_partition(ary, start, end, pivotIndex);
inplace_quicksort(ary, start, pivotIndex - 1);
inplace_quicksort(ary, pivotIndex + 1, end);
}
return ary;
}
// Heap sort
function heapSort(ary) {
heapify(ary);
for (var end = ary.length - 1; end > 0; end--) {
swap(ary, end, 0);
shiftDown(ary, 0, end - 1);
}
return ary;
}
function heapify(ary) {
for (var start = (ary.length >> 1) - 1; start >= 0; start--) {
shiftDown(ary, start, ary.length - 1);
}
}
function shiftDown(ary, start, end) {
var root = start,
child, s;
while (root * 2 + 1 <= end) {
child = root * 2 + 1;
s = root;
if (ary[s] < ary[child]) {
s = child;
}
if (child + 1 <= end && ary[s] < ary[child + 1]) {
s = child + 1;
}
if (s !== root) {
swap(ary, root, s);
root = s;
} else {
return;
}
}
}
// Merge sort
function merge_sort(ary) {
if (ary.length <= 1) {
return ary;
}
var m = ary.length >> 1;
var left = ary.slice(0, m),
right = ary.slice(m);
return merge(merge_sort(left), merge_sort(right));
}
function merge(left, right) {
var result = [],
li = 0, ri = 0;
while (li < left.length || ri < right.length) {
if (li < left.length && ri < right.length) {
if (left[li] <= right[ri]) {
result.push(left[li]);
li++;
} else {
result.push(right[ri]);
ri++;
}
} else if (li < left.length) {
result.push(left[li]);
li++;
} else if (ri < right.length) {
result.push(right[ri]);
ri++;
}
}
return result;
}
// Shell sort
function shell_sort(ary) {
var inc = Math.round(ary.length / 2),
i, j, t;
while (inc > 0) {
for (i = inc; i < ary.length; i++) {
t = ary[i];
j = i;
while (j >= inc && ary[j - inc] > t) {
ary[j] = ary[j - inc];
j -= inc;
}
ary[j] = t;
}
inc = Math.round(inc / 2.2);
}
return ary;
}
//Comb Sort (Basically bubblesort with a small modification, but heaps faster)
function comb_sort(ary) {
var gap = ary.length;
while(true) {
gap = newgap(gap);
var swapped = false;
for(var i=0,l=ary.length;i<l;i++) {
var j = i + gap;
if(ary[i] < ary[j]) {
swap(ary,i,j);
swapped = true;
}
}
if(gap == 1 && !swapped)
break;
}
return ary;
}
function newgap(gap) {
gap = ((gap * 10) / 13) | 0;
if(gap == 9 || gap == 10)
gap = 11;
if(gap < 1)
gap = 1;
return gap;
}
//faster quicksort using a stack to eliminate recursion, sorting inplace to reduce memory usage, and using insertion sort for small partition sizes
function fast_quicksort(ary) {
var stack = [];
var entry = [0,ary.length,2 * Math.floor(Math.log(ary.length)/Math.log(2))];
stack.push(entry);
while(stack.length > 0) {
entry = stack.pop();
var start = entry[0];
var end = entry[1];
var depth = entry[2];
if(depth == 0) {
ary = shell_sort_bound(ary,start,end);
continue;
}
depth--;
var pivot = Math.round((start + end) / 2);
var pivotNewIndex = inplace_quicksort_partition(ary,start,end, pivot);
if(end - pivotNewIndex > 16) {
entry = [pivotNewIndex,end,depth];
stack.push(entry);
}
if(pivotNewIndex - start > 16) {
entry = [start,pivotNewIndex,depth];
stack.push(entry);
}
}
ary = insertion_sort(ary);
return ary;
}
function shell_sort_bound(ary,start,end) {
var inc = Math.round((start + end)/2),
i, j, t;
while (inc >= start) {
for (i = inc; i < end; i++) {
t = ary[i];
j = i;
while (j >= inc && ary[j - inc] > t) {
ary[j] = ary[j - inc];
j -= inc;
}
ary[j] = t;
}
inc = Math.round(inc / 2.2);
}
return ary;
}
function mSort(list) {
if (list.length < 14) {
return insertion_sort(list);
}
var half = Math.floor(list.length / 2);
var a = mSort(list.slice(0, half));
var b = mSort(list.slice(half, list.length));
var aCount = 0;
var bCount = 0;
var returnList = [];
while (true) {
if (a[aCount] <= b[bCount]) {
returnList.push(a[aCount]);
aCount++;
if (aCount === a.length) {
returnList = returnList.concat(b.slice(bCount, b.length));
break;
}
}
else {
returnList.push(b[bCount]);
bCount++;
if (bCount === b.length) {
returnList = returnList.concat(a.slice(aCount, a.length));
break;
}
}
}
return returnList;
}
function bubbleSort(items) {
var length = items.length;
for (var i = 0; i < length; i++) { //Number of passes
for (var j = 0; j < (length - i - 1); j++) { //Notice that j < (length - i)
//Compare the adjacent positions
if(items[j] > items[j+1]) {
//Swap the numbers
var tmp = items[j]; //Temporary variable to hold the current number
items[j] = items[j+1]; //Replace current number with adjacent number
items[j+1] = tmp; //Replace adjacent number with current number
}
}
}
}
https://stackoverflow.com/a/38979903/8769328
function radixBucketSort (arr) {
var idx1, idx2, idx3, len1, len2, radix, radixKey;
var radices = {}, buckets = {}, num, curr;
var currLen, radixStr, currBucket;
len1 = arr.length;
len2 = 10; // radix sort uses ten buckets
// find the relevant radices to process for efficiency
for (idx1 = 0;idx1 < len1;idx1++) {
radices[arr[idx1].toString().length] = 0;
}
// loop for each radix. For each radix we put all the items
// in buckets, and then pull them out of the buckets.
for (radix in radices) {
// put each array item in a bucket based on its radix value
len1 = arr.length;
for (idx1 = 0;idx1 < len1;idx1++) {
curr = arr[idx1];
// item length is used to find its current radix value
currLen = curr.toString().length;
// only put the item in a radix bucket if the item
// key is as long as the radix
if (currLen >= radix) {
// radix starts from beginning of key, so need to
// adjust to get redix values from start of stringified key
radixKey = curr.toString()[currLen - radix];
// create the bucket if it does not already exist
if (!buckets.hasOwnProperty(radixKey)) {
buckets[radixKey] = [];
}
// put the array value in the bucket
buckets[radixKey].push(curr);
} else {
if (!buckets.hasOwnProperty('0')) {
buckets['0'] = [];
}
buckets['0'].push(curr);
}
}
// for current radix, items are in buckets, now put them
// back in the array based on their buckets
// this index moves us through the array as we insert items
idx1 = 0;
// go through all the buckets
for (idx2 = 0;idx2 < len2;idx2++) {
// only process buckets with items
if (buckets[idx2] != null) {
currBucket = buckets[idx2];
// insert all bucket items into array
len1 = currBucket.length;
for (idx3 = 0;idx3 < len1;idx3++) {
arr[idx1++] = currBucket[idx3];
}
}
}
buckets = {};
}
}
var input = [];
for (var i = 0; i < 1000; i++) {
input[i] = Math.round(Math.random() * 1000000);
}
@2bam
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2bam commented May 7, 2023

Chrome 112 - i7-6700HQ Skylake - Windows 10.

For 1000x random numbers

  • Fast QuickSort x 24,842 ops/sec ±1.68% (36 runs sampled)
  • Inplace Quicksort x 18,402 ops/sec ±6.55% (36 runs sampled)
  • Heap Sort x 15,566 ops/sec ±1.02% (43 runs sampled)
  • Built-in Sort x 4,591 ops/sec ±1.73% (29 runs sampled)

For 1000 almost ordered (10 out of order)

  • Fast QuickSort | Fast QuickSort x 97,980 ops/sec ±1.12% (65 runs sampled)
  • Insertion Sort | Insertion Sort x 83,391 ops/sec ±1.09% (59 runs sampled)
  • Inplace Quicksort | Inplace Quicksort x 38,242 ops/sec ±0.91% (65 runs sampled)
  • Built-in Sort | Built-in Sort x 17,134 ops/sec ±1.70% (64 runs sampled)

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