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Get input value by looping name selector

I want to loop through a list of element which have dynamic name's value, like item1,item2 etc. but I got undefined like below.
len = $('.aws').length + 1;
var obj = [],
temp = {};
for (var i = 1; i <= len; i++) {
console.log(i)
temp["index"] = $('.aws[name="item' + i + '"]').val()
obj.push(temp);
}
console.log(obj);
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<input type="hidden" class="aws" name="item1" value="1.jpg">
<input type="hidden" class="aws" name="item2" value="2.jpg">

The problem is that you're pushing a reference to the same object on each iteration. In doing so, the index property on the temp object will be the value from the last iteration.
In addition, there are only two elements, and the for loop was executed three times because of the condition i <= len (it should have been i < len). Due to this, the value was undefined on the last iteration, because the element doesn't exist. This resulted in all the index properties on the temp property being set to undefined.
If you want a native JS solution, you could simply use the following instead:
var elements = document.querySelectorAll('.aws');
var values = [];
for (var i = 0; i < elements.length; i++) {
values.push({index: elements[i].value});
}
In the snippet above, a new object is pushed to the values array on each iteration (rather than a reference to the same object). The for loop condition is also i < elements.length (rather than i <= elements.length), so it will only iterate 2 times (rather than 3 like in your example).
If you want a shorter jQuery solution, simply use the .map() method:
var values = $('.aws').map(function () {
return {index: this.value };
}).get();

Try this: https://jsfiddle.net/Twisty/ys889cn6/1/
var obj = [],
temp = {};
$(document).ready(function() {
$(".aws").each(function(i, v) {
obj.push({ "index": $(this).val() });
});
console.log(obj);
});
Much easier to loop this way. Read more: https://api.jquery.com/each/
Somewhat Native
$(document).ready(function() {
var obj = [],
temp = {},
len = $('.aws').length;
for (var i = 0; i < len; i++) {
console.log("Get Value from: .aws[name='item" + (i+1) + "']");
temp["index"] = $(".aws[name='item" + (i+1) + "']").val();
obj.push(temp);
}
console.log(obj);
});
As #PatrickEvans stated, we're just dropping the same object in. Results:
Get Value from: .aws[name='item1']
Get Value from: .aws[name='item2']
[Object { index="2.jpg"}, Object { index="2.jpg"}]
Fixed by using:
$(document).ready(function() {
var obj = [],
temp = {},
len = $('.aws').length;
for (var i = 0; i < len; i++) {
console.log("Get Value from: .aws[name='item" + (i+1) + "']");
obj.push({"index": $(".aws[name='item" + (i+1) + "']").val()});
}
console.log(obj);
});

Arrays Splice Pop Shift Read

I create an array like so
var membersList = $('#chatbox_members' , avacweb_chat.doc.body).find('li');
var onlineUsers = [];
var offLineUsers = [];
for(var i =0;i<membersList.length;i++){
var name = $(membersList[i]).text().replace("#","");
onlineUsers.push(name);
}
alert(onlineUsers);
listedUsers would come out something like so [Mr.EasyBB,Tonight,Tomorrow,Gone];
Question is if I use a two for loops one outside a setInterval and one inside to compare-
var membersList = $('#chatbox_members' , _chat.doc.body).find('li');
var onlineUsers = [];
var offLineUsers= [];
for(var i =0;i<membersList.length;i++){
var name = $(membersList[i]).text().replace("#","");
onlineUsers.push(name);
}
var int = setInterval(function() {
var newMember = ('#chatbox_members' , _chat.doc.body).find('li');
for(var i =0;i<newMember.length;i++){
var name = $(newMember[i]).text().replace("#","");
offLineUsers.push(name);
}
Which then would get:
onlineUsers = [Mr.EasyBB,Tonight,Tomorrow,Gone];
offLineUsers = [Mr.EasyBB,Tonight];
So to get the offline users I want to basically replace onlineUsers with offLineUsers which then should return Tomorrow,Gone . Though I know that an object doesn't have the function to replace so how would I go about this?
I don't think the splice function would work since you need to have parameters, and pop or shift are beginning and end of array.

for(var i = 0 ; i < offLineUsers.length ; i++)
{
for(var j = 0 ; j < onlineUsers.length ; j++)
{
if(onlineUsers[j] == offLineUsers[i])
{
onlineUsers.splice(j,1);
}
}
}
Try this snippet.

If I have understand well, maybe that helps:
function bus_dup() {
for(var i = 0; i < offLineUsers.length; i++) {
onLineUsers.splice(onLineUsers.indexOf(offLineUsers[i]),1);
}
offLineUsers = [];
}

This should do what you are looking for on a modern browser, using array.filter
var onlineUsers = ["Mr.EasyBB", "Tonight", "Tomorrow", "Gone"];
var offLineUsers = ["Mr.EasyBB", "Tonight"];
function discord(online, offline) {
return online.filter(function (element) {
return offline.indexOf(element) === -1;
});
}
console.log(discord(onlineUsers, offLineUsers));
Output
["Tomorrow", "Gone"]
On jsfiddle
If you want the difference regardless of the order of attributes passed to the function then you could do this.
var onlineUsers = ["Mr.EasyBB", "Tonight", "Tomorrow", "Gone"];
var offLineUsers = ["Mr.EasyBB", "Tonight"];
function difference(array1, array2) {
var a = array1.filter(function (element) {
return array2.indexOf(element) === -1;
});
var b = array2.filter(function (element) {
return array1.indexOf(element) === -1;
});
return a.concat(b);
}
console.log(difference(onlineUsers, offLineUsers));
console.log(difference(offLineUsers, onlineUsers));
Output
["Tomorrow", "Gone"] 
["Tomorrow", "Gone"] 
On jsfiddle

Array length undefined after split

I'd like to split a string ("1,2,3") and return it as an int array so I wrote the following function:
function stringToIntArray(string) {
var split = {};
split = string.split(',');
var selected = {};
for (var i = 0; i <= split.length; i++) {
selected[i] = split[i];
}
return selected;
}
However split.length is always undefinied. Where's my mistake?

var selected = {};
doesn't build an array but an object, which has no length property.
You can fix your code by replacing it with
var selected = [];
If you want to return an array of numbers, you can change your code to
function stringToIntArray(string) {
var split = string.split(',');
var selected = [];
for (var i = 0; i < split.length; i++) {
selected.push(parseInt(split[i], 10));
}
return selected;
}
Note that I replaced <= with < in your loop.
Note also that for modern browsers, you can use the map function to make it simpler :
function stringToIntArray(string) {
return string.split(',').map(function(v){ return parseInt(v, 10) });
}

Count how many strings in an array have duplicates in the same array [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Array value count javascript
I have an array which contains several duplicates, what I'm trying to achieve is to count how many duplicates each unique string has in this one array.
The array looks something like this
array = ['aa','bb','cc','aa','ss','aa','bb'];
Thus I would like to do something like this
if (xWordOccurrences >= 5) {
// do something
}
But I'm not sure how I would code this.
I was thinking, create an object with each unique string, then loop through the original array, match each string with it's object and increment it's number by 1, then loop over the object to see which words had the most duplicates...
But this seems like an over complexe way to do it.

You can use an object which has keys of the Array's values and do something like this
// count everything
function getCounts(arr) {
var i = arr.length, // var to loop over
obj = {}; // obj to store results
while (i) obj[arr[--i]] = (obj[arr[i]] || 0) + 1; // count occurrences
return obj;
}
// get specific from everything
function getCount(word, arr) {
return getCounts(arr)[word] || 0;
}
getCount('aa', ['aa','bb','cc','aa','ss','aa','bb']);
// 3
If you only ever want to get one, then it'd be more a bit more efficient to use a modified version of getCounts which looks similar to getCount, I'll call it getCount2
function getCount2(word, arr) {
var i = arr.length, // var to loop over
j = 0; // number of hits
while (i) if (arr[--i] === word) ++j; // count occurance
return j;
}
getCount2('aa', ['aa','bb','cc','aa','ss','aa','bb']);
// 3

Try this function:
var countOccurrences = function(arr,value){
var len = arr.length;
var occur = 0;
for(var i=0;i<len;i++){
if(arr[i]===value){
occur++;
}
}
return occur;
}
var count = countOccurrences(['aaa','bbb','ccc','bbb','ddd'],'bbb'); //2
If you want, you can also add this function to the Array prototype:
Array.prototype.countOccurrences = function(value){
var len = this.length;
var occur = 0;
for(var i=0;i<len;i++){
if(this[i]===value){
occur++;
}
}
return occur;
}

How about you build an object with named property?
var array = ['aa','bb','cc','aa','ss','aa','bb'];
var summary = {};
var item = '';
for ( i in array){
item = array[i];
if(summary[item]){
summary[item] += 1;
}
else{
summary[item] = 1;
}
}
console.log( summary );
summary will contain like this
{aa: 3, bb: 2, cc: 1, ss: 1}
which you could then iterate on and then sort them later on if needed.
finally to get your count, you could use this summary['aa']

<script type="text/javascript">
var array = ['aa','bb','cc','aa','ss','aa','bb'];
var myMap = {};
for(i = 0; i < array.length; i++) {
var count = myMap[array[i]];
if(count != null) {
count++;
} else {
count = 1;
}
myMap[array[i]] = count;
}
// at this point in the script, the map now contains each unique array item and a count of its entries
</script>

Hope this solves your problem
var array = ['aa','bb','cc','aa','ss','aa','bb'];
var dups = {};
for (var i = 0, l = array.length; i < l; i++ ) {
dups[array[i]] = [];
}
for (str in dups) {
for (var i = 0, l = array.length; i < l; i++ ) {
if (str === array[i]) {
dups[str].push(str);
}
}
}
for (str in dups) {
console.log(str + ' has ' + (dups[str].length - 1) + ' duplicate(s)');
}

This function may do everything you need.
function countDupStr(arr, specifier) {
var count = {}, total = 0;
arr.forEach(function (v) {
count[v] = (count[v] || 0) + 1;
});
if(typeof specifier !== 'undefined') {
return count[specifier] - 1;
}
Object.keys(count).forEach(function (k) {
total += count[k] - 1;
});
return total;
}
Each value in the array is assigned and incremented to the count object. Whether or not a specifier was passed, the function will return duplicates of that specific string or the total number of duplicates. Note that this particular technique will only work on string-coercible values inside your arrays, as Javascript can only index objects by string.
What this means is that during object assignment, the keys will normalize down to strings and cannot be relied upon for uniqueness. That is to say, this function wouldn't be able to discern the difference between duplicates of 3 and '3'. To give an example, if I were to perform:
var o = {}, t = {};
o[t] = 1;
console.log(o);
The key used in place of t would eventually be t.toString(), thus resulting in the perhaps surprising object of {'[object Object]': 1}. Just something to keep in mind when working with Javascript properties.

I saw this post about it, perhaps it can help:
http://ryanbosinger.com/blog/2011/javascript-count-duplicates-in-an-array/

Remove duplicate element pairs from multidimensional array

I have an array that looks like this:
1. coordinates = [ [16.343345, 35.123523],
2. [14.325423, 34.632723],
3. [15.231512, 35.426914],
4. [16.343345, 35.123523],
5. [15.231512, 32.426914] ]
The latitude on line 5 is the same as on line 3, but they have different longitudes and are therefore not duplicates.
Both the latitude and longitude are the same on line 3 and 6, and are therefore duplicates and one should be removed.

The difficulty in this question that different arrays never compare equal even if they contain same values. Therefore direct comparison methods, like indexOf won't work.
The following pattern might be useful to solve this. Write a function (or use a built-in one) that converts arrays to scalar values and checks if these values are unique in a set.
uniq = function(items, key) {
var set = {};
return items.filter(function(item) {
var k = key ? key.apply(item) : item;
return k in set ? false : set[k] = true;
})
}
where key is a "hash" function that convert items (whatever they are) to comparable scalar values. In your particular example, it seems to be enough just to apply Array.join to arrays:
uniqueCoords = uniq(coordinates, [].join)

You can use standard javascript function splice for this.
for(var i = 0; i < coordinates.length; i++) {
for(var j = i + 1; j < coordinates.length; ) {
if(coordinates[i][0] == coordinates[j][0] && coordinates[i][1] == coordinates[j][1])
// Found the same. Remove it.
coordinates.splice(j, 1);
else
// No match. Go ahead.
j++;
}
}
However, if you have thousands of points it will work slowly, than you need to consider to sort values at first, then remove duplicates in one loop.

I rewrote the answer from thg435 (It does not allow me to post comments) and prototype it also using jQuery instead, so this will work on all browsers using it (Even IE7)
Array.prototype.uniq = function (key) {
var set = {};
return $.grep(this, function (item) {
var k = key
? key.apply(item)
: item;
return k in set
? false
: set[k] = true;
});
}
You can use it like:
arr = arr.uniq([].join);

If you are not on Safari this single liner could do the job
var arr = [[16.343345, 35.123523],
[14.325423, 34.632723],
[15.231512, 35.426914],
[16.343345, 35.123523],
[15.231512, 32.426914]],
lut = {},
red = arr.filter(a => lut[a] ? false : lut[a] = true);
document.write("<pre>" + JSON.stringify(red,null,2) + "</pre>");

It might be simpler to create another array keeping only unique coordinate pairs
var uniqueCoors = [];
var doneCoors = [];
for(var x = 0; x < coordinates.length; x++) {
var coorStr = coordinates[x].toString();
if(doneCoors.indexOf(coorStr) != -1) {
// coordinate already exist, ignore
continue;
}
doneCoors.push(coorStr);
uniqueCoors.push(coordinates[x]);
}

function sortCoordinates(arr){
var obj = {};
for(var i = 0, l = arr.length; i < l; i++){
var el = arr[i];
var lat = el[0];
var lng = el[1];
if(!obj[lat + lng]){
obj[lat + lng] = [lat, lng];
}
}
var out = [];
for(p in obj){
out.push([obj[p][0], obj[p][1]]);
}
return out;
}

I am not sure about coordinates[][] dataType. Make the comparison accordingly.
var dubJRows= new Array();
for(int i = 0; i < coordinates.length -2; i++){
for(int j = i+1; j < coordinates.length -1; j++){
if (i != j && chk_dubJRows_not_contains(j)) {
innerArray1 [1][1] = coordinates[i];
innerArray2 [1][1] = coordinates[j];
if ( innerArray1 [1][0] == innerArray2[1][0]
&& innerArray1[1][1] == innerArray2[1][1]) {
dubJRows.push(j);
}
}
}
}
//REMOVE ALL dubJRows from coordinates.