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How to simplify this delete from array jQuery

I have an object and an array of categories that should be kept in the object. This snip https://jsfiddle.net/h10rkb6s/2/ ( see log ) works but I cant seems to shake the idea that it is to complicated for a simple search and keep task.
var thz_icon_source = {"Spinners":["spinnericon1","spinnericon2"],"Awesome":["awesomeicon1","awesomeicon2"],"Others":["othericon1","othericon2"]};
var $categories = '["Spinners","Awesome"]';
var $CatsArray = JSON.parse($categories);
var groups = [];
for(var k in thz_icon_source) groups.push(k);
$.each($CatsArray,function(i,keep){
var index = groups.indexOf(keep);
if (index !== -1) {
groups.splice(index, 1);
}
});
for (var i = 0; i < groups.length; i++) {
delete thz_icon_source[groups[i]];
}
I tried with
$.each(thz_icon_source,function(category,icons){
$.each($CatsArray,function(i,keep){
var index = category.indexOf(keep);
if (index !== -1) {
delete thz_icon_source[category];
}
});
});
but this works only if 1 item is inside my search array.
Any help is appreciated.

There's no need to iterate over $CatsArray to find out which ones should be deleted. You will need to iterate over the keys of the object, and find out for each of them whether it should be deleted, to filter by that.
Leaving the top 3 lines of your script intact, you could simplify to
var keysToDelete = Object.keys(thz_icon_source).filter(function(groupName) {
return $CatsArray.indexOf(groupName) == -1;
});
($.grep would be the jQuery-ism for the filter method, if you are into that).
But assuming we don't even need those groups in an array, you could simply do
for (var groupName in thz_icon_source)
if ($CatsArray.indexOf(groupName) == -1)
delete thz_icon_source[groupName];
However, instead of deleting items from that object, I'd recommend to create a new object with only those that you want to keep. It's much easier to use:
var kept = {};
for (var i=0; i<$CatsArray.length; i++)
kept[$CatsArray[i]] = thz_icon_source[$CatsArray[i]];

cannot iterate through array and change value in JS

I have to iterate through an array, change one of its values, and create another array refelecting the changes.
this is what I have so far:
JS:
var arr = new Array();
arr['t1'] = "sdfsdf";
arr['t2'] = "sdfsdf";
arr['t3'] = "sdfsdf";
arr['t4'] = "sdfsdf";
arr['t5'] = "sdfsdf";
var last = new Array();
for (var i = 0; i <= 5; i++) {
arr['t2'] = i;
last.push(arr);
}
console.log(last);
Unfortunately, these are my results
As you can see, I am not getting the results needed as 0,1,2.. instead I am getting 2, 2, 2..
This is what i would like my results to be:
How can I fix this?

You have to make a copy, otherwise you are dealing with reference to the same object all the time. As it was said before - javascript does not have associate arrays, only objects with properties.
var arr = {}; // empty object
arr['t1'] = "sdfsdf";
arr['t2'] = "sdfsdf";
arr['t3'] = "sdfsdf";
arr['t4'] = "sdfsdf";
arr['t5'] = "sdfsdf";
var last = new Array();
for (var i = 0; i <= 5; i++) {
var copy = JSON.parse(JSON.stringify(arr)); //create a copy, one of the ways
copy['t2'] = i; // set value of its element
last.push(copy); // push copy into last
}
console.log(last);
ps: you can use dot notation arr.t1 instead of arr['t1']

The array access with ['t2'] is not the problem. This is a regular JavaScript feature.
The problem is: You are adding the SAME array to "last" (5 times in code, 3 times in the screenshot).
Every time you set ['t2'] = i, you will change the values in "last" also, because they are actually just references to the same array-instance.
You must create a copy/clone of the array before you add it to "last".
This is what will happen in all languages where arrays are references to objects (Java, C#...). It would work with C++ STL though.

Sorting 2D javascript array

I have an array containing a list of tags and count.
tags_array[0] = tags;
tags_array[1] = tags_count;
I need to sort the arrays base on the count so that I can pick out the top few tags.

Sort one, while storing the sort comparisons. Then sort the other using those results:
var res = [];
tags_count.sort( function( a, b ){ return res.push( a=a-b ), a; } );
tags.sort( function(){ return res.shift(); } );

Supposing tags and tags_count are 2 arrays of same length, I would first build a proper array of objects :
var array = [];
for (var i=0; i<tags_count.length; i++) {
array.push({tag:tags[i], count:tags_count[i]});
}
And then sort on the count :
array.sort(function(a, b) {return a.count-b.count});
If you need to get your arrays back after that, you may do
for (var i=0; i<array.length; i++) {
tags[i] = array[i].tag;
tags_count[i] = array[i].count;
}
Demonstration

Assuming that both tags and tags_count are arrays with the same length (that part of the question wasn't too clear), the following is one way to do the trick.
var tags_array = new Array();
for (var i = 0; i < tags.length; i++)
{
tags_array[i] = {};
tags_array[i].tagName = tags[i];
tags_array[i].tagCount = tags_count[i];
}
tags_array.sort(function(a,b){return b.tagCount-a.tagCount});
One should note that it might be possible to structure the data in this way from the start instead of rewriting it like this, in which case that is preferable. Likewise, a better structure can be used to save the data, but this will work.

How to "clean" an array in javascript?

I am stuck here. How can I clean this array:
{"data":[{"id":"5201521d42"},{"id":"52049e2591"},{"id":"52951699w4"}]}
So that it looks like:
["5201521d42","52049e2591","52951699w4"]
I am using Javascript.

You just need to iterate over the existing data array and pull out each id value and put it into a new "clean" array like this:
var raw = {"data":[{"":"5201521d42"},{"id":"52049e2591"},{"id":"52951699w4"}]};
var clean = [];
for (var i = 0, len = raw.data.length; i < len; i++) {
clean.push(raw.data[i].id);
}

Overwriting the same object
var o = {"data":[{"id":"5201521d42"},{"id":"52049e2591"},{"id":"52951699w4"}]};
for (var i = o.data.length; i--; ){
o.data[i] = o.data[i].id;
}
What you're doing is replacing the existing object with the value of its id property.

If you can use ES5 and performance is not critical, i would recommend this:
Edit:
Looking at this jsperf testcase, map vs manual for is about 7-10 times slower, which actually isn't that much considering that this is already in the area of millions of operations per second. So under the paradigma of avoiding prematurely optimizations, this is a lot cleaner and the way forward.
var dump = {"data":[{"id":"5201521d42"},{"id":"52049e2591"},{"id":"52951699w4"}]};
var ids = dump.data.map(function (v) { return v.id; });
Otherwise:
var data = dump.data;
var ids = [];
for (var i = 0; i < data.length; i++) {
ids.push(data[i].id);
}

Do something like:
var cleanedArray = [];
for(var i=0; i<data.length; i++) {
cleanedArray.push(data[i].id);
}
data = cleanedArray;

Take a look at this fiddle. I think this is what you're looking for
oldObj={"data":[{"":"5201521d42"},{"id":"52049e2591"},{"id":"52951699w4"}]};
oldObj = oldObj.data;
myArray = [];
for (var key in oldObj) {
var obj = oldObj[key];
for (var prop in obj) {
myArray.push(obj[prop]);
}
}
console.log(myArray)

Use Array.prototype.map there is fallback code defined in this documentation page that will define the function if your user's browser is missing it.

var data = {"data":[{"":"5201521d42"},{"id":"52049e2591"},{"id":"52951699w4"}]};
var clean_array = [];
for( var i in data.data )
{
for( var j in data.data[i] )
{
clean_array.push( data.data[i][j] )
}
}
console.log( clean_array );

You are actually reducing dimension. or you may say you are extracting a single dimension from the qube. you may even say selecting a column from an array of objects. But the term clean doesn't match with your problem.
var list = [];
var raw = {"data":[{"id":"5201521d42"},{"id":"52049e2591"},{"id":"52951699w4"}]};
for(var i=0; i < raw.data.length ; ++i){
list.push(raw.data[i].id);
}

Use the map function on your Array:
data.map(function(item) { return item.id; });
This will return:
["5201521d42", "52049e2591", "52951699w4"]
What is map? It's a method that creates a new array using the results of the provided function. Read all about it: map - MDN Docs

The simplest way to clean any ARRAY in javascript
its using a loop for over the data or manually, like this:
let data = {"data":[{"id":"5201521d42"},{"id":"52049e2591"},
{"id":"52951699w4"}]};
let n = [data.data[0].id,data.data[1].id, data.data[2].id];
console.log(n)
output:
(3) ["5201521d42", "52049e2591", "52951699w4"]

Easy and a clean way to do this.
oldArr = {"data":[{"id":"5201521d42"},{"id":"52049e2591"},{"id":"52951699w4"}]}
oldArr = oldArr["data"].map(element => element.id)
Output: ['5201521d42', '52049e2591', '52951699w4']

How to separate the values from two dimension array in js?

jQuery.get("ChkNewRspLive.php?lastmsgID=" + n, function(newitems){
//some code to separate values of 2d array.
$('#div1').append(msgid);
$('#div2').append(rspid);
});
Let's say the value of newitems is [["320","23"],["310","26"]]
I want to assign "320" and "310" to var msgid.
I want to assign "23" and "26" to var rspid.
How to do that?
I tried to display newitems and the output is "Array". I tried to display newitems[0] and the output is blank.
If I redeclare var newitems = [["320","23"],["310","26"]]; it works. So I guess the variable newitems from jQuery.get is something wrong. Is it I cannot pass the array from other page to current page through jQuery directly?
Regarding the array on other page, if echo json_encode($Arraytest); the output is [["320","23"],["310","26"]] but if echo $Arraytest; the output is Array. How do I pass the array from other page to currently page by jQuery.get?

I don't totally understand the question but I'm going to assume you want the values in an array, as two values can't be stored in one (scalar) variable simultaneously.
jQuery.get("ChkNewRspLive.php?lastmsgID=" + n, function(newitems){
//some code to separate values of 2d array.
var msgid = [],
rspid = [];
for( i = 0 ; i < newitems.length ; i++){
msgid[msgid.length] = newitems[i][0];
rspid[rspid.length] = newitems[i][1];
}
//msgid now contains ["320","310"]
//rspid now contains ["23","26"]
});
Bear in mind those are in the function scope. If you want to use them outside of that scope instantiate them outside. see: closure

You can use pluck from underscore.js: http://documentcloud.github.com/underscore/#pluck
var msgid = _(newitems).pluck(0)
var rspid = _(newitems).pluck(1)

Try this:
function getArrayDimension(arr, dim) {
var res = [];
for(var i = 0; i < arr.length; i++) {
res.push(arr[i][dim]);
}
return res;
}
var newitems = [["320","23"],["310","26"]];
var msgid = getArrayDimension(newitems, 0);
var rspid = getArrayDimension(newitems, 1);
msgid and rspid are arrays holding the 'nth' dimention.
Tnx