Mots clés : javascriptarraysduplicatesuniquejavascript
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uniq = [...new Set(array)];
uniqueArray = a.filter(function(item, pos) { return a.indexOf(item) == pos; })
uniqueArray = a.filter(function(item, pos, self) { return self.indexOf(item) == pos; })
function uniq(a) { var seen = {}; return a.filter(function(item) { return seen.hasOwnProperty(item) ? false : (seen[item] = true); }); }
function uniq(a) { var prims = {"boolean":{}, "number":{}, "string":{}}, objs = []; return a.filter(function(item) { var type = typeof item; if(type in prims) return prims[type].hasOwnProperty(item) ? false : (prims[type][item] = true); else return objs.indexOf(item) >= 0 ? false : objs.push(item); }); }
function uniq(a) { return a.sort().filter(function(item, pos, ary) { return !pos || item != ary[pos - 1]; }); }
function uniqBy(a, key) { var seen = {}; return a.filter(function(item) { var k = key(item); return seen.hasOwnProperty(k) ? false : (seen[k] = true); }) }
a = [[1,2,3], [4,5,6], [1,2,3]] b = uniqBy(a, JSON.stringify) console.log(b) // [[1,2,3], [4,5,6]]
function uniqBy(a, key) { var index = []; return a.filter(function (item) { var k = key(item); return index.indexOf(k) >= 0 ? false : index.push(k); }); }
function uniqBy(a, key) { let seen = new Set(); return a.filter(item => { let k = key(item); return seen.has(k) ? false : seen.add(k); }); }
function uniqBy(a, key) { return [ ...new Map( a.map(x => [key(x), x]) ).values() ] }
function uniqByKeepFirst(a, key) { let seen = new Set(); return a.filter(item => { let k = key(item); return seen.has(k) ? false : seen.add(k); }); } function uniqByKeepLast(a, key) { return [ ...new Map( a.map(x => [key(x), x]) ).values() ] } // data = [ {a:1, u:1}, {a:2, u:2}, {a:3, u:3}, {a:4, u:1}, {a:5, u:2}, {a:6, u:3}, ]; console.log(uniqByKeepFirst(data, it => it.u)) console.log(uniqByKeepLast(data, it => it.u))
var result = []; a.forEach(function(item) { if(result.indexOf(item) < 0) { result.push(item); } });
$.uniqArray = function(a) { return $.grep(a, function(item, pos) { return $.inArray(item, a) === pos; }); }
function uniq_fast(a) { var seen = {}; var out = []; var len = a.length; var j = 0; for(var i = 0; i < len; i++) { var item = a[i]; if(seen[item] !== 1) { seen[item] = 1; out[j++] = item; } } return out; }
function uniq(a) { var seen = {}; return a.filter(function(item) { return seen.hasOwnProperty(item) ? false : (seen[item] = true); }); } function uniq_fast(a) { var seen = {}; var out = []; var len = a.length; var j = 0; for(var i = 0; i < len; i++) { var item = a[i]; if(seen[item] !== 1) { seen[item] = 1; out[j++] = item; } } return out; } ///// var r = [0,1,2,3,4,5,6,7,8,9], a = [], LEN = 1000, LOOPS = 1000; while(LEN--) a = a.concat(r); var d = new Date(); for(var i = 0; i < LOOPS; i++) uniq(a); document.write('<br>uniq, ms/loop: ' + (new Date() - d)/LOOPS) var d = new Date(); for(var i = 0; i < LOOPS; i++) uniq_fast(a); document.write('<br>uniq_fast, ms/loop: ' + (new Date() - d)/LOOPS)
function uniq(a) { return Array.from(new Set(a)); }
let uniq = a => [...new Set(a)];
function* uniqIter(a) { let seen = new Set(); for (let x of a) { if (!seen.has(x)) { seen.add(x); yield x; } } } // example: function* randomsBelow(limit) { while (1) yield Math.floor(Math.random() * limit); } // note that randomsBelow is endless count = 20; limit = 30; for (let r of uniqIter(randomsBelow(limit))) { console.log(r); if (--count === 0) break } // exercise for the reader: what happens if we set `limit` less than `count` and why
80
var names = ["Mike","Matt","Nancy","Adam","Jenny","Nancy","Carl"]; var uniqueNames = []; $.each(names, function(i, el){ if($.inArray(el, uniqueNames) === -1) uniqueNames.push(el); });
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var names = ["Mike","Matt","Nancy","Adam","Jenny","Nancy","Carl"]; var uniq = names.reduce(function(a,b){ if (a.indexOf(b) < 0 ) a.push(b); return a; },[]); console.log(uniq, names) // [ 'Mike', 'Matt', 'Nancy', 'Adam', 'Jenny', 'Carl' ] // one liner return names.reduce(function(a,b){if(a.indexOf(b)<0)a.push(b);return a;},[]);
var uniq = names.slice() // slice makes copy of array before sorting it .sort(function(a,b){ return a > b; }) .reduce(function(a,b){ if (a.slice(-1)[0] !== b) a.push(b); // slice(-1)[0] means last item in array without removing it (like .pop()) return a; },[]); // this empty array becomes the starting value for a // one liner return names.slice().sort(function(a,b){return a > b}).reduce(function(a,b){if (a.slice(-1)[0] !== b) a.push(b);return a;},[]);
var uniq = [ ...new Set(names) ]; // [ 'Mike', 'Matt', 'Nancy', 'Adam', 'Jenny', 'Carl' ]
var names = ['Mike', 'Matt', 'Nancy', 'Adam', 'Jenny', 'Nancy', 'Carl'] var uniq = names .map((name) => { return {count: 1, name: name} }) .reduce((a, b) => { a[b.name] = (a[b.name] || 0) + b.count return a }, {}) var sorted = Object.keys(uniq).sort((a, b) => uniq[a] < uniq[b]) console.log(sorted)
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function remove_duplicates(arr) { var obj = {}; var ret_arr = []; for (var i = 0; i < arr.length; i++) { obj[arr[i]] = true; } for (var key in obj) { ret_arr.push(key); } return ret_arr; }
function remove_duplicates_safe(arr) { var seen = {}; var ret_arr = []; for (var i = 0; i < arr.length; i++) { if (!(arr[i] in seen)) { ret_arr.push(arr[i]); seen[arr[i]] = true; } } return ret_arr; }
function remove_duplicates_es6(arr) { let s = new Set(arr); let it = s.values(); return Array.from(it); }
a = ["Mike","Matt","Nancy","Adam","Jenny","Nancy","Carl"]; b = remove_duplicates(a); // b: // ["Adam", "Carl", "Jenny", "Matt", "Mike", "Nancy"] c = remove_duplicates_safe(a); // c: // ["Mike", "Matt", "Nancy", "Adam", "Jenny", "Carl"] d = remove_duplicates_es6(a); // d: // ["Mike", "Matt", "Nancy", "Adam", "Jenny", "Carl"]
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arr = arr.filter(function (value, index, array) { return array.indexOf(value) === index; });