How to sort an array of integers correctly
JavascriptArraysSortingNumbersJavascript Problem Overview
Trying to get the highest and lowest value from an array that I know will contain only integers seems to be harder than I thought.
var numArray = [140000, 104, 99];
numArray = numArray.sort();
console.log(numArray)
I'd expect this to show 99, 104, 140000. Instead it shows 104, 140000, 99. So it seems the sort is handling the values as strings.
Is there a way to get the sort function to actually sort on integer value?
Javascript Solutions
Solution 1 - Javascript
By default, the sort method sorts elements alphabetically. To sort numerically just add a new method which handles numeric sorts (sortNumber, shown below) -
var numArray = [140000, 104, 99];
numArray.sort(function(a, b) {
return a - b;
});
console.log(numArray);
Documentation:
Mozilla Array.prototype.sort() recommends this compare function for arrays that don't contain Infinity or NaN. (Because Infinity - Infinity is NaN, not 0).
Also examples of sorting objects by key.
Solution 2 - Javascript
Just building on all of the above answers, they can also be done in one line like this:
var numArray = [140000, 104, 99];
numArray = numArray.sort(function (a, b) { return a - b; });
//outputs: 99, 104, 140000
Solution 3 - Javascript
I am surprised why everyone recommends to pass a comparator function to sort(), that makes sorting really slow!
To sort numbers, just create any TypedArray:
var numArray = new Float64Array([140000, 104, 99]);
numArray = numArray.sort();
console.log(numArray)
Solution 4 - Javascript
array.sort does a lexicographic sort by default, for a numeric sort, provide your own function. Here's a simple example:
function compareNumbers(a, b)
{
return a - b;
}
numArray.sort(compareNumbers);
Also note that sort works "in place", there's no need for the assignment.
Solution 5 - Javascript
This answer is equivalent to some of the existing answers, but ECMAScript 6 arrow functions provide a much more compact syntax that allows us to define an inline sort function without sacrificing readability:
numArray = numArray.sort((a, b) => a - b);
It is supported in most browsers today.
Solution 6 - Javascript
The reason why the sort function behaves so weird
From the documentation:
> [...] the array is sorted according to each character's Unicode code point > value, according to the string conversion of each element.
If you print the unicode point values of the array then it will get clear.
console.log("140000".charCodeAt(0));
console.log("104".charCodeAt(0));
console.log("99".charCodeAt(0));
//Note that we only look at the first index of the number "charCodeAt( 0 )"
This returns: "49, 49, 57".
49 (unicode value of first number at 140000)
49 (unicode value of first number at 104)
57 (unicode value of first number at 99)
Now, because 140000 and 104 returned the same values (49) it cuts the first index and checks again:
console.log("40000".charCodeAt(0));
console.log("04".charCodeAt(0));
//Note that we only look at the first index of the number "charCodeAt( 0 )"
52 (unicode value of first number at 40000)
40 (unicode value of first number at 04)
If we sort this, then we will get:
40 (unicode value of first number at 04)
52 (unicode value of first number at 40000)
so 104 comes before 140000.
So the final result will be:
var numArray = [140000, 104, 99];
numArray = numArray.sort();
console.log(numArray)
104, 140000, 99
Conclusion:
sort() does sorting by only looking at the first index of the numbers. sort() does not care if a whole number is bigger than another, it compares the value of the unicode of the digits, and if there are two equal unicode values, then it checks if there is a next digit and compares it as well.
To sort correctly, you have to pass a compare function to sort() like explained here.
Solution 7 - Javascript
I agree with aks, however instead of using
return a - b;
You should use
return a > b ? 1 : a < b ? -1 : 0;
Solution 8 - Javascript
just do .sort((a, b) => a - b) instead of .sort() itself
var numArray = [140000, 104, 99];
numArray.sort((a, b) => a - b);
console.log(numArray)
Solution 9 - Javascript
In JavaScript the sort() method's default behaviour is to sort values in an array alphabetically.
To sort by number you have to define a numeric sort function (which is very easy):
...
function sortNumber(a, b)
{
return a - b;
}
numArray = numArray.sort(sortNumber);
Solution 10 - Javascript
Ascending
arr.sort((a, b) => a - b);
Descending
arr.sort((a, b) => b - a);
Just for fun:
Descending = Ascending + Reverse
arr.sort((a, b) => a - b).reverse();
Solution 11 - Javascript
Array.prototype.sort() is the go to method for sorting arrays, but there are a couple of issues we need to be aware of.
The sorting order is by default lexicographic and not numeric regardless of the types of values in the array. Even if the array is all numbers, all values will be converted to string and sorted lexicographically.
So should we need to customize the sort() and reverse() method like below.
For sorting numbers inside the array
numArray.sort(function(a, b)
{
return a - b;
});
For reversing numbers inside the array
numArray.sort(function(a, b)
{
return b - a;
});
Solution 12 - Javascript
The question has already been answered, the shortest way is to use sort() method. But if you're searching for more ways to sort your array of numbers, and you also love cycles, check the following
Insertion sort
Ascending:
var numArray = [140000, 104, 99];
for (var i = 0; i < numArray.length; i++) {
var target = numArray[i];
for (var j = i - 1; j >= 0 && (numArray[j] > target); j--) {
numArray[j+1] = numArray[j];
}
numArray[j+1] = target
}
console.log(numArray);
Descending:
var numArray = [140000, 104, 99];
for (var i = 0; i < numArray.length; i++) {
var target = numArray[i];
for (var j = i - 1; j >= 0 && (numArray[j] < target); j--) {
numArray[j+1] = numArray[j];
}
numArray[j+1] = target
}
console.log(numArray);
Selection sort:
Ascending:
var numArray = [140000, 104, 99];
for (var i = 0; i < numArray.length - 1; i++) {
var min = i;
for (var j = i + 1; j < numArray.length; j++) {
if (numArray[j] < numArray[min]) {
min = j;
}
}
if (min != i) {
var target = numArray[i];
numArray[i] = numArray[min];
numArray[min] = target;
}
}
console.log(numArray);
Descending:
var numArray = [140000, 104, 99];
for (var i = 0; i < numArray.length - 1; i++) {
var min = i;
for (var j = i + 1; j < numArray.length; j++) {
if (numArray[j] > numArray[min]) {
min = j;
}
}
if (min != i) {
var target = numArray[i];
numArray[i] = numArray[min];
numArray[min] = target;
}
}
console.log(numArray);
Have fun
Solution 13 - Javascript
The function 'numerically' below serves the purpose of sorting array of numbers numerically in many cases when provided as a callback function:
function numerically(a, b){
return a-b;
}
array.sort(numerically);
But in some rare instances, where array contains very large and negative numbers, an overflow error can occur as the result of a-b gets smaller than the smallest number that JavaScript can cope with.
So a better way of writing numerically function is as follows:
function numerically(a, b){
if(a < b){
return -1;
} else if(a > b){
return 1;
} else {
return 0;
}
}
Solution 14 - Javascript
to handle undefined, null, and NaN: Null behaves like 0, NaN and undefined goes to end.
array = [3, 5, -1, 1, NaN, 6, undefined, 2, null]
array.sort((a,b) => isNaN(a) || a-b)
// [-1, null, 1, 2, 3, 5, 6, NaN, undefined]
Solution 15 - Javascript
While not required in JavaScript, if you would like the sort() compareFunction to strictly return -1, 0, or 1 (similar to how the spaceship operator works in PHP), then you can use Math.sign().
The compareFunction below strictly returns -1, 0, or 1:
numArray.sort((a, b) => Math.sign(a - b));
> Note: Math.sign() is not supported in Internet Explorer.
Solution 16 - Javascript
For a normal array of elements values only:
function sortArrayOfElements(arrayToSort) {
function compareElements(a, b) {
if (a < b)
return -1;
if (a > b)
return 1;
return 0;
}
return arrayToSort.sort(compareElements);
}
e.g. 1:
var array1 = [1,2,545,676,64,2,24]
**output : [1, 2, 2, 24, 64, 545, 676]**
var array2 = ["v","a",545,676,64,2,"24"]
**output: ["a", "v", 2, "24", 64, 545, 676]**
For an array of objects:
function sortArrayOfObjects(arrayToSort, key) {
function compareObjects(a, b) {
if (a[key] < b[key])
return -1;
if (a[key] > b[key])
return 1;
return 0;
}
return arrayToSort.sort(compareObjects);
}
e.g. 1: var array1= [{"name": "User4", "value": 4},{"name": "User3", "value": 3},{"name": "User2", "value": 2}]
**output : [{"name": "User2", "value": 2},{"name": "User3", "value": 3},{"name": "User4", "value": 4}]**
Solution 17 - Javascript
> Update! Scroll to bottom of answer for smartSort prop additive that gives even more fun!
Sorts arrays of anything!
My personal favorite form of this function allows for a param for Ascending, or Descending:
function intArraySort(c, a) {
function d(a, b) { return b - a; }
"string" == typeof a && a.toLowerCase();
switch (a) {
default: return c.sort(function(a, b) { return a - b; });
case 1:
case "d":
case "dc":
case "desc":
return c.sort(d)
}
};
Usage as simple as:
var ara = function getArray() {
var a = Math.floor(Math.random()*50)+1, b = [];
for (i=0;i<=a;i++) b.push(Math.floor(Math.random()*50)+1);
return b;
}();
// Ascending
intArraySort(ara);
console.log(ara);
// Descending
intArraySort(ara, 1);
console.log(ara);
// Ascending
intArraySort(ara, 'a');
console.log(ara);
// Descending
intArraySort(ara, 'dc');
console.log(ara);
// Ascending
intArraySort(ara, 'asc');
console.log(ara);
jsFiddle
Or Code Snippet Example Here!
function intArraySort(c, a) {
function d(a, b) { return b - a }
"string" == typeof a && a.toLowerCase();
switch (a) {
default: return c.sort(function(a, b) { return a - b });
case 1:
case "d":
case "dc":
case "desc":
return c.sort(d)
}
};
function tableExample() {
var d = function() {
var a = Math.floor(50 * Math.random()) + 1,
b = [];
for (i = 0; i <= a; i++) b.push(Math.floor(50 * Math.random()) + 1);
return b
},
a = function(a) {
var b = $("<tr/>"),
c = $("<th/>").prependTo(b);
$("<td/>", {
text: intArraySort(d(), a).join(", ")
}).appendTo(b);
switch (a) {
case 1:
case "d":
case "dc":
case "desc":
c.addClass("desc").text("Descending");
break;
default:
c.addClass("asc").text("Ascending")
}
return b
};
return $("tbody").empty().append(a(), a(1), a(), a(1), a(), a(1), a(), a(1), a(), a(1), a(), a(1))
};
tableExample();
table { border-collapse: collapse; }
th, td { border: 1px solid; padding: .25em .5em; vertical-align: top; }
.asc { color: red; }
.desc { color: blue }
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<table><tbody></tbody></table>
.smartSort('asc' | 'desc')
Now have even more fun with a sorting method that sorts an array full of multiple items! Doesn't currently cover "associative" (aka, string keys), but it does cover about every type of value! Not only will it sort the multiple values asc or desc accordingly, but it will also maintain constant "position" of "groups" of values. In other words; ints are always first, then come strings, then arrays (yes, i'm making this multidimensional!), then Objects (unfiltered, element, date), & finally undefineds and nulls!
"Why?" you ask. Why not!
Now comes in 2 flavors! The first of which requires newer browsers as it uses Object.defineProperty to add the method to the Array.protoype Object. This allows for ease of natural use, such as: myArray.smartSort('a'). If you need to implement for older browsers, or you simply don't like modifying native Objects, scroll down to Method Only version.
/* begin */
/* KEY NOTE! Requires EcmaScript 5.1 (not compatible with older browsers) */
;;(function(){if(Object.defineProperty&&!Array.prototype.smartSort){var h=function(a,b){if(null==a||void 0==a)return 1;if(null==b||void 0==b)return-1;var c=typeof a,e=c+typeof b;if(/^numbernumber$/ig.test(e))return a-b;if(/^stringstring$/ig.test(e))return a>b;if(/(string|number){2}/ig.test(e))return/string/i.test(c)?1:-1;if(/number/ig.test(e)&&/object/ig.test(e)||/string/ig.test(e)&&/object/ig.test(e))return/object/i.test(c)?1:-1;if(/^objectobject$/ig.test(e)){a instanceof Array&&a.smartSort("a");b instanceof Array&&b.smartSort("a");if(a instanceof Date&&b instanceof Date)return a-b;if(a instanceof Array&&b instanceof Array){var e=Object.keys(a),g=Object.keys(b),e=e.concat(g).smartSort("a"),d;for(d in e)if(c=e[d],a[c]!=b[c])return d=[a[c],b[c]].smartSort("a"),a[c]==d[0]?-1:1;var f=[a[Object.keys(a)[0]],b[Object.keys(b)[0]]].smartSort("a");return a[Object.keys(a)[0]]==f[0]?-1:1}if(a instanceof Element&&b instanceof Element){if(a.tagName==b.tagName)return e=[a.id,b.id].smartSort("a"),a.id==e[0]?1:-1;e=[a.tagName, b.tagName].smartSort("a");return a.tagName==e[0]?1:-1}if(a instanceof Date||b instanceof Date)return a instanceof Date?1:-1;if(a instanceof Array||b instanceof Array)return a instanceof Array?-1:1;e=Object.keys(a);g=Object.keys(b);e.concat(g).smartSort("a");for(c=0;20>c;c++){d=e[c];f=g[c];if(a.hasOwnProperty(d)&&b.hasOwnProperty(f)){if(a[d]instanceof Element&&b[f]instanceof Element){if(a[d].tagName==b[f].tagName)return c=[a[d].id,b[f].id].smartSort("a"),a[d].id==c[0]?-1:1;c=[a[d].tagName,b[f].tagName].smartSort("d"); return a[d].tagName==c[0]?1:-1}if(a[d]instanceof Element||b[f]instanceof Element)return a[d]instanceof Element?1:-1;if(a[d]!=b[f])return c=[a[d],b[f]].smartSort("a"),a[d]==c[0]?-1:1}if(a.hasOwnProperty(d)&&a[d]instanceof Element)return 1;if(b.hasOwnProperty(f)&&b[f]instanceof Element||!a.hasOwnProperty(d))return-1;if(!b.hasOwnProperty(d))return 1}c=[a[Object.keys(a)[0]],b[Object.keys(b)[0]]].smartSort("d");return a[Object.keys(a)[0]]==c[0]?-1:1}g=[a,b].sort();return g[0]>g[1]},k=function(a,b){if(null== a||void 0==a)return 1;if(null==b||void 0==b)return-1;var c=typeof a,e=c+typeof b;if(/^numbernumber$/ig.test(e))return b-a;if(/^stringstring$/ig.test(e))return b>a;if(/(string|number){2}/ig.test(e))return/string/i.test(c)?1:-1;if(/number/ig.test(e)&&/object/ig.test(e)||/string/ig.test(e)&&/object/ig.test(e))return/object/i.test(c)?1:-1;if(/^objectobject$/ig.test(e)){a instanceof Array&&a.smartSort("d");b instanceof Array&&b.smartSort("d");if(a instanceof Date&&b instanceof Date)return b-a;if(a instanceof Array&&b instanceof Array){var e=Object.keys(a),g=Object.keys(b),e=e.concat(g).smartSort("a"),d;for(d in e)if(c=e[d],a[c]!=b[c])return d=[a[c],b[c]].smartSort("d"),a[c]==d[0]?-1:1;var f=[a[Object.keys(a)[0]],b[Object.keys(b)[0]]].smartSort("d");return a[Object.keys(a)[0]]==f[0]?-1:1}if(a instanceof Element&&b instanceof Element){if(a.tagName==b.tagName)return e=[a.id,b.id].smartSort("d"),a.id==e[0]?-1:1;e=[a.tagName,b.tagName].smartSort("d");return a.tagName==e[0]?-1:1}if(a instanceof Date||b instanceof Date)return a instanceof Date?1:-1;if(a instanceof Array||b instanceof Array)return a instanceof Array?-1:1;e=Object.keys(a);g=Object.keys(b);e.concat(g).smartSort("a");for(c=0;20>c;c++){d=e[c];f=g[c];if(a.hasOwnProperty(d)&&b.hasOwnProperty(f)){if(a[d]instanceof Element&&b[f]instanceof Element){if(a[d].tagName==b[f].tagName)return c=[a[d].id,b[f].id].smartSort("d"),a[d].id==c[0]?-1:1;c=[a[d].tagName,b[f].tagName].smartSort("d");return a[d].tagName==c[0]?-1:1}if(a[d]instanceof Element||b[f]instanceof Element)return a[d]instanceof Element?1:-1;if(a[d]!=b[f])return c=[a[d],b[f]].smartSort("d"),a[d]==c[0]?-1:1}if(a.hasOwnProperty(d)&&a[d]instanceof Element)return 1;if(b.hasOwnProperty(f)&&b[f]instanceof Element)return-1;if(!a.hasOwnProperty(d))return 1;if(!b.hasOwnProperty(d))return-1}c=[a[Object.keys(a)[0]],b[Object.keys(b)[0]]].smartSort("d");return a[Object.keys(a)[0]]==c[0]?-1:1}g=[a,b].sort();return g[0]<g[1]};Object.defineProperty(Array.prototype,"smartSort",{value:function(){return arguments&& (!arguments.length||1==arguments.length&&/^a([sc]{2})?$|^d([esc]{3})?$/i.test(arguments[0]))?this.sort(!arguments.length||/^a([sc]{2})?$/i.test(arguments[0])?h:k):this.sort()}})}})();
/* end */
jsFiddle Array.prototype.smartSort('asc|desc')
Use is simple! First make some crazy array like:
window.z = [ 'one', undefined, $('<span />'), 'two', null, 2, $('<div />', { id: 'Thing' }), $('<div />'), 4, $('<header />') ];
z.push(new Date('1/01/2011'));
z.push('three');
z.push(undefined);
z.push([ 'one', 'three', 'four' ]);
z.push([ 'one', 'three', 'five' ]);
z.push({ a: 'a', b: 'b' });
z.push({ name: 'bob', value: 'bill' });
z.push(new Date());
z.push({ john: 'jill', jack: 'june' });
z.push([ 'abc', 'def', [ 'abc', 'def', 'cba' ], [ 'cba', 'def', 'bca' ], 'cba' ]);
z.push([ 'cba', 'def', 'bca' ]);
z.push({ a: 'a', b: 'b', c: 'c' });
z.push({ a: 'a', b: 'b', c: 'd' });
Then simply sort it!
z.smartSort('asc'); // Ascending
z.smartSort('desc'); // Descending
Method Only
Same as the preceding, except as just a simple method!
/* begin */
/* KEY NOTE! Method `smartSort` is appended to native `window` for global use. If you'd prefer a more local scope, simple change `window.smartSort` to `var smartSort` and place inside your class/method */
window.smartSort=function(){if(arguments){var a,b,c;for(c in arguments)arguments[c]instanceof Array&&(a=arguments[c],void 0==b&&(b="a")),"string"==typeof arguments[c]&&(b=/^a([sc]{2})?$/i.test(arguments[c])?"a":"d");if(a instanceof Array)return a.sort("a"==b?smartSort.asc:smartSort.desc)}return this.sort()};smartSort.asc=function(a,b){if(null==a||void 0==a)return 1;if(null==b||void 0==b)return-1;var c=typeof a,e=c+typeof b;if(/^numbernumber$/ig.test(e))return a-b;if(/^stringstring$/ig.test(e))return a> b;if(/(string|number){2}/ig.test(e))return/string/i.test(c)?1:-1;if(/number/ig.test(e)&&/object/ig.test(e)||/string/ig.test(e)&&/object/ig.test(e))return/object/i.test(c)?1:-1;if(/^objectobject$/ig.test(e)){a instanceof Array&&a.sort(smartSort.asc);b instanceof Array&&b.sort(smartSort.asc);if(a instanceof Date&&b instanceof Date)return a-b;if(a instanceof Array&&b instanceof Array){var e=Object.keys(a),g=Object.keys(b),e=smartSort(e.concat(g),"a"),d;for(d in e)if(c=e[d],a[c]!=b[c])return d=smartSort([a[c], b[c]],"a"),a[c]==d[0]?-1:1;var f=smartSort([a[Object.keys(a)[0]],b[Object.keys(b)[0]]],"a");return a[Object.keys(a)[0]]==f[0]?-1:1}if(a instanceof Element&&b instanceof Element){if(a.tagName==b.tagName)return e=smartSort([a.id,b.id],"a"),a.id==e[0]?1:-1;e=smartSort([a.tagName,b.tagName],"a");return a.tagName==e[0]?1:-1}if(a instanceof Date||b instanceof Date)return a instanceof Date?1:-1;if(a instanceof Array||b instanceof Array)return a instanceof Array?-1:1;e=Object.keys(a);g=Object.keys(b);smartSort(e.concat(g), "a");for(c=0;20>c;c++){d=e[c];f=g[c];if(a.hasOwnProperty(d)&&b.hasOwnProperty(f)){if(a[d]instanceof Element&&b[f]instanceof Element){if(a[d].tagName==b[f].tagName)return c=smartSort([a[d].id,b[f].id],"a"),a[d].id==c[0]?-1:1;c=smartSort([a[d].tagName,b[f].tagName],"a");return a[d].tagName==c[0]?-1:1}if(a[d]instanceof Element||b[f]instanceof Element)return a[d]instanceof Element?1:-1;if(a[d]!=b[f])return c=smartSort([a[d],b[f]],"a"),a[d]==c[0]?-1:1}if(a.hasOwnProperty(d)&&a[d]instanceof Element)return 1; if(b.hasOwnProperty(f)&&b[f]instanceof Element||!a.hasOwnProperty(d))return-1;if(!b.hasOwnProperty(d))return 1}c=smartSort([a[Object.keys(a)[0]],b[Object.keys(b)[0]]],"a");return a[Object.keys(a)[0]]==c[0]?1:-1}g=[a,b].sort();return g[0]>g[1]};smartSort.desc=function(a,b){if(null==a||void 0==a)return 1;if(null==b||void 0==b)return-1;var c=typeof a,e=c+typeof b;if(/^numbernumber$/ig.test(e))return b-a;if(/^stringstring$/ig.test(e))return b>a;if(/(string|number){2}/ig.test(e))return/string/i.test(c)? 1:-1;if(/number/ig.test(e)&&/object/ig.test(e)||/string/ig.test(e)&&/object/ig.test(e))return/object/i.test(c)?1:-1;if(/^objectobject$/ig.test(e)){a instanceof Array&&a.sort(smartSort.desc);b instanceof Array&&b.sort(smartSort.desc);if(a instanceof Date&&b instanceof Date)return b-a;if(a instanceof Array&&b instanceof Array){var e=Object.keys(a),g=Object.keys(b),e=smartSort(e.concat(g),"a"),d;for(d in e)if(c=e[d],a[c]!=b[c])return d=smartSort([a[c],b[c]],"d"),a[c]==d[0]?-1:1;var f=smartSort([a[Object.keys(a)[0]], b[Object.keys(b)[0]]],"d");return a[Object.keys(a)[0]]==f[0]?-1:1}if(a instanceof Element&&b instanceof Element){if(a.tagName==b.tagName)return e=smartSort([a.id,b.id],"d"),a.id==e[0]?-1:1;e=smartSort([a.tagName,b.tagName],"d");return a.tagName==e[0]?-1:1}if(a instanceof Date||b instanceof Date)return a instanceof Date?1:-1;if(a instanceof Array||b instanceof Array)return a instanceof Array?-1:1;e=Object.keys(a);g=Object.keys(b);smartSort(e.concat(g),"a");for(c=0;20>c;c++){d=e[c];f=g[c];if(a.hasOwnProperty(d)&& b.hasOwnProperty(f)){if(a[d]instanceof Element&&b[f]instanceof Element){if(a[d].tagName==b[f].tagName)return c=smartSort([a[d].id,b[f].id],"d"),a[d].id==c[0]?-1:1;c=smartSort([a[d].tagName,b[f].tagName],"d");return a[d].tagName==c[0]?-1:1}if(a[d]instanceof Element||b[f]instanceof Element)return a[d]instanceof Element?1:-1;if(a[d]!=b[f])return c=smartSort([a[d],b[f]],"d"),a[d]==c[0]?-1:1}if(a.hasOwnProperty(d)&&a[d]instanceof Element)return 1;if(b.hasOwnProperty(f)&&b[f]instanceof Element)return-1; if(!a.hasOwnProperty(d))return 1;if(!b.hasOwnProperty(d))return-1}c=smartSort([a[Object.keys(a)[0]],b[Object.keys(b)[0]]],"d");return a[Object.keys(a)[0]]==c[0]?-1:1}g=[a,b].sort();return g[0]<g[1]}
/* end */
Use:
z = smartSort(z, 'asc'); // Ascending
z = smartSort(z, 'desc'); // Descending
jsFiddle Method smartSort(Array, "asc|desc")
Solution 18 - Javascript
Try this code:
HTML:
<div id="demo"></div>
JavaScript code:
<script>
(function(){
var points = [40, 100, 1, 5, 25, 10];
document.getElementById("demo").innerHTML = points;
points.sort(function(a, b){return a-b});
document.getElementById("demo").innerHTML = points;
})();
</script>
Solution 19 - Javascript
Try this code as below
var a = [5, 17, 29, 48, 64, 21];
function sortA(arr) {
return arr.sort(function(a, b) {
return a - b;
})
;}
alert(sortA(a));
Solution 20 - Javascript
TypeScript variant
const compareNumbers = (a: number, b: number): number => a - b
myArray.sort(compareNumbers)
Solution 21 - Javascript
In order to create this kind of sort, you have to pass a function that will check which comes first.
define inside the function which value do you wanna check: a.id - a.id
const myJson = [
{ id: 1, name: 'one'},
{ id: 4, name: 'four'},
{ id: 2, name: 'two'},
{ id: 3, name: 'three'}
];
// provide the sort method to check
const myNewSort = myJson.sort(function(a, b) {
return a.id - b.id;
});
console.log('my new sort',myNewSort)
Solution 22 - Javascript
The accepted answer and equivalents like numArray.sort((a,b) => a - b) are great when the array contains only numbers without infinities or NaN. They can be extended to handle infinities and NaN like so:
numArray.sort((a,b) => (+a || 0) - (+b || 0) || 0);
This sorts NaN (or any non-number, like 'foo' or {}) as if it were 0. The final || 0 is needed to handle the case where a and b are equal infinities.
Solution 23 - Javascript
sort_mixed
Object.defineProperty(Array.prototype,"sort_mixed",{
value: function () { // do not use arrow function
var N = [], L = [];
this.forEach(e => {
Number.isFinite(e) ? N.push(e) : L.push(e);
});
N.sort((a, b) => a - b);
L.sort();
[...N, ...L].forEach((v, i) => this[i] = v);
return this;
})
try a =[1,'u',"V",10,4,"c","A"].sort_mixed(); console.log(a)
Solution 24 - Javascript
If anyone doesn't understand how Array.sort() works with integers, read this answer.
Alphabetical order:
By default, the sort() method sorts the values as strings in alphabetical and ascending order.
const myArray = [104, 140000, 99];
myArray.sort();
console.log(myArray); // output is [104, 140000, 99]
Ascending order with array.sort(compareFunction):
const myArray = [104, 140000, 99];
myArray.sort(function(a, b){
return a - b;
});
console.log(myArray); // output is [99, 104, 140000]
Explanation from w3schools:
> compareFunction defines an alternative sort order. The function should return a negative, zero, or positive value, depending on the arguments, like:
function(a, b){return a-b}
When the sort() method compares two values, it sends the values to the compare function, and sorts the values according to the returned (negative, zero, positive) value.
>
> Example:
>
> When comparing 40 and 100, the sort() method calls the compare
> function(40,100).
>
> The function calculates 40-100, and returns -60 (a negative value).
>
> The sort function will sort 40 as a value lower than 100.
Descending order with array.sort(compareFunction):
const myArray = [104, 140000, 99];
myArray.sort(function(a, b){
return b - a;
});
console.log(myArray); // output is [140000, 104, 99]
This time we calculated with b - a(i.e., 100-40) which returns a positive value.
Solution 25 - Javascript
You can sort number array simply by
const num=[13,17,14,19,16];
let temp;
for(let i=0;i<num.length;i++){
for(let j=i+1;j<num.length;j++){
if(num[i]>num[j]){
temp=num[i]
num[i]=num[j]
num[j]=temp
}
}
}
console.log(num);
Solution 26 - Javascript
You can get height and lowest number simply by using max() and min() in-built function
var numArray = [140000, 104, 99];
console.log(Math.max(...numArray));
console.log(Math.min(...numArray));
If you want to sort in ascending or descending order
numArray.sort((a, b)=> a - b);
Solution 27 - Javascript
If you need to calculate and sort the largest charCodeAt from a list of string this is the right way.
const arrayLines = '1.1.1.1\n1.0.1.1\n1.1.1.2\n1.1.1.0'.split('\n');
// Response: (4) ['1.0.1.1', '1.1.1.0', '1.1.1.1', '1.1.1.2']
arrayLines.sort((a, b) => {
let a_charCodeSize = 0,
b_charCodeSize = 0;
// Loop true a & b characters and calculate the charCodeAt size.
for (const aChar of a) a_charCodeSize += aChar.charCodeAt(0);
for (const bChar of b) b_charCodeSize += bChar.charCodeAt(0);
return a_charCodeSize - b_charCodeSize;
});
Solution 28 - Javascript
As sort method converts Array elements into string. So, below way also works fine with decimal numbers with array elements.
let productPrices = [10.33, 2.55, 1.06, 5.77];
console.log(productPrices.sort((a,b)=>a-b));
And gives you the expected result.
Solution 29 - Javascript
Sort integers > 0, think outside the box:
function sortArray(arr) {
return new Promise((resolve) => {
const result = []
arr.forEach((item) => {
setTimeout(() => {
result.push(item)
if (result.length === arr.length) resolve(result)
}, item)
})
})
}
sortArray([4, 2, 42, 128, 56, 2]).then((result) => {
document.write(JSON.stringify(result))
})
> Note that this should not be used productively, .sort() is better suited for this, check the other answers
Solution 30 - Javascript
-
Ascending
const movements = [200, 450, -400, 3000, -650, -130, 70, 1300];
If we return something < 0 then A will be before B If we return something > 0 then B will be before A
movements.sort((a, b) => {
if (a > b) return 1; //- (Switch order)
if (a < b) return -1; //- (Keep order)
});
a - current value, b - the next value.
-
Descending
movements.sort((a, b) => { if (a > b) return -1; // - (Keep) if (a < b) return 1; // - (Switch) });
! Improve, best solution !
movements.sort ((a, b) => a - b); // Same result!
If a < b it's negative number(Switch) If a < b it's negative number(Keep)