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Javascript - Adding multiple values to keys

I am trying to find the places of each letter in a sentence by using "dictionaries". The problem is I want to find all the places that each letter is and not only the last one. I am very new to JavaScript and couldn't figure out the way to do it.
function letters(stringArgument) {
stringArgument = stringArgument.replace(/ /g,'');
var dict = {};
for (var i=0; i < stringArgument.length; i++ )
if (!stringArgument[i] in dict){
dict[stringArgument[i]] = [];
}else{
dict[stringArgument[i]] = [i+1]
}
return dict
}
var a = letters('Lost time is never found again.');
console.log(a);
naturally gives this output:
{ L: [ 1 ], o: [ 17 ], s: [ 10 ], t: [ 5 ]...
but it should give this:
{ L: [ 1 ], o: [ 2, 17 ], s: [ 3, 10 ], t: [ 4, 5 ]...
Also each letter is saved to the dictionary at the same order they appear in the sentence, how can I order the letters alphabetically?

What you need is a function that gets the positions of a character in a given string.
Try this:
function findAllPositions(char, content) {
var result = [];
let index = content.indexOf(char);
while(index !== -1) {
result.push(index);
index = content.indexOf(char, index + 1);
}
return result;
}
findAllPositions('o', 'Lost time is never found again.'); // Result =  [1, 20]
Using this we can update the letter function as follows:
function letters(stringArgument) {
stringArgument = stringArgument.replace(/ /g, '');
var dict = {};
for (const char of stringArgument) {
dict[char] = findAllPositions(char, stringArgument)
}
return dict;
}
letters('is again.')
/*
{
"i": [0, 5],
"s": [1],
"a": [2, 4],
"g": [3],
"n": [6],
".": [7]
}
*/

You need to have
parantheses for the check
if (!(stringArgument[i] in dict)) {
create an array if the above is true
push the postion to the array
For getting a sorted output, you could take the entries of the object, apply a sorting by taking the key and show the result in order.
Object have an insertation oder for not positive 32 bit numbers (like indixes) or symbols. The index like numbers are sorted by value and appears first in the object.
function letters(stringArgument) {
stringArgument = stringArgument.replace(/ /g, '');
var dict = {};
for (var i = 0; i < stringArgument.length; i++) {
if (!(stringArgument[i] in dict)) {
dict[stringArgument[i]] = [];
}
dict[stringArgument[i]].push(i + 1);
}
return dict;
}
var a = letters('Lost time is never found again.');
Object
.entries(a)
.sort(([a], [b]) => a.localeCompare(b))
.forEach(([key, positions]) => console.log(key, ...positions));
console.log(a);

First, for any item, if it is not in an empty array:
var notInDict = !(stringArgument[i] in dict);
If not in dict, then initialize an empty array and push the item in it using
dict[stringArgument[i]].push(i + 1);
Try this.
function letters(stringArgument) {
stringArgument = stringArgument.replace(/ /g, "");
var dict = {};
for (var i = 0; i < stringArgument.length; i++) {
var notInDict = !(stringArgument[i] in dict);
if (notInDict) {
dict[stringArgument[i]] = [];
}
dict[stringArgument[i]].push(i + 1);
}
return dict;
}
var a = letters("Lost time is never found again.");
console.log(a);

you are assigning a new array at each iteration
dict[stringArgument[i]] = [i+1]
what you need to do is push the new position to existing array.
dict[stringArgument[i]].push(i+1)
also, remove the else block
function letters(stringArgument) {
stringArgument = stringArgument.toLowerCase().replace(/ /g,'');
var dict = {};
for (var i=0; i < stringArgument.length; i++ ){
if (!dict.hasOwnProperty(stringArgument[i])){
dict[stringArgument[i]] = [];
}
dict[stringArgument[i]].push(i+1);
}
//sorting
var letters = Object.keys(dict); //returns a array
letters.sort();
var sortedDic = {};
for(var i in letters) {
sortedDic[letters[i]] = dict[letters[i]];
}
return sortedDic;
}
var a = letters('Lost time is never found again.');
console.log(a);

for the first part you can also do that:
let sentence = 'Lost time is never found again.'
let tabLetters = [...sentence.replace(/ /g,'')].reduce((a,c,i)=>
{
if (!a[c]) a[c] = [i+1]
else a[c].push(i+1)
return a
},{})
document.write(JSON.stringify(tabLetters))

Sum of same object name in javascript

Hi friends I'm beginner for javascript how i sum same n no's of object name corresponding value and push the result to new array.see this is sample object
var obj_1 ={'delivered':10,'due':11,'team_name':'UK'};
var obj_2 ={'delivered':10,'due':11,'team_name':'US'};
var obj_nth ={'delivered':10,'due':11,'team_name':'UK'};
but i expect this output [UK:{'delivered':20,'due':22},US:{'delivered':10,'due':11}],so please help me what i'll do next

You can first create array of objects and then reduce() to return one object.
var obj_1 ={'delivered':10,'due':11,'team_name':'UK'};
var obj_2 ={'delivered':10,'due':11,'team_name':'US'};
var obj_nth ={'delivered':10,'due':11,'team_name':'UK'};
var result = [obj_1, obj_2, obj_nth].reduce(function(r, e) {
if(!r[e.team_name]) {
r[e.team_name] = {delivered:0,due:0}
}
r[e.team_name].delivered += e.delivered
r[e.team_name].due += e.due
return r
}, {})
console.log(result)

const newArray = initialArray.map(({team_name, ...restProps}) => {
return {
[team_name]: {...restProps}
};
});
See:
Arrow functions
Spread operator
Array.prototype.map
Computed property names

var obj_1 ={'delivered':10,'due':11,'team_name':'UK'};
var obj_2 ={'delivered':10,'due':11,'team_name':'US'};
var obj_nth ={'delivered':10,'due':11,'team_name':'UK'};
function sum_all() {
var sum={};
for(var i=0;i<arguments.length;i++) {
obj = arguments[i];
if (!sum[obj.team_name]) {
sum[obj.team_name]={'delivered':0,'due':0};
}
sum[obj.team_name].delivered += obj.delivered;
sum[obj.team_name].due += obj.due;
}
return sum;
}
var sum = sum_all(obj_1,obj_2,obj_nth);
console.log(sum);
Your console output will be:
sum
Object
UK: Object
delivered: 20
due: 22
US: Object
delivered: 10
due: 11

Store these objects in an array, such as:
var myObjects = [
{'delivered':10,'due':11,'team_name':'UK'},
{'delivered':10,'due':11,'team_name':'US'},
{'delivered':10,'due':11,'team_name':'UK'}
];
Create a new object in which you will store your results:
var results = {};
Then iterate through the array with a for loop (as it is generally faster) and add the other properties according to team_name:
for (var i = 0; i <= myObjects.length; i++) {
if (typeof results[myObjects[i].team_name] !== undefined) {
results[myObjects[i]].delivered += myObjects[i].delivered;
results[myObjects[i]].due += myObjects[i].due;
} else {
// Set 0 to these properties if the entry didn't exist
results[myObjects[i]].delivered = 0;
results[myObjects[i]].due = 0;
}
}

Store count of integers in order using javascript

I have string like the following:
11222233344444445666
What I would like to do is output the number followed the times it was displayed:
112433475163
Question is, I want this to be efficient. I can store this in an object as the following:
1: { id: 1, displayed: 2},
2: { id: 2, displayed: 1},
3: { id: 3, displayed: 2},
etc.
I can access this object and increment displayed.
My issues is, there is no guarantee in the order. I would like to store the keys in the order they are in the string. How do I accomplish the importance of the order in the object?

This is a proposal for run length coding with an array which holds infomation about one charcter and the count of it:
{
"char": "1",
"count": 2
},
var string = "11222233344444445666",
array = function () {
var r = [], o = {};
string.split('').forEach(function (a, i, aa) {
if (a !== aa[i - 1]) {
o[a] = { char: a, count: 0 };
r.push(o[a]);
}
o[a].count++;
});
return r;
}(string);
document.write('<pre>' + JSON.stringify(array, 0, 4) + '</pre>');

Quick solution with for loop:
var str = "7771122229933344444445666",
obj = {},
len = str.length,
val = null,
count_str = "",
key = "";
for (var i = 0; i < len; i++) {
val = str[i], key = 'k' + val;
if (!obj[key]) {
obj[key] = {'id': val, 'displayed': 1};
} else {
obj[key].displayed++;
}
}
for (var p in obj) {
count_str += obj[p]['id'] + obj[p]['displayed'];
}
console.log(count_str); // "7312249233475163"

because you have such a small set of distinct numbers, I seen no reason why you can't use a array (yeah it's not super ideal memorywise if you skip values and it becomes sparse, but for such a small subset it won't affect you enough to worry of it). Then you can use (number-1) as the index and increment that number as needed.
var counts = [];
var str = "11222233344444445666";
for(var i in str){
var index = parseInt(str[i])-1
counts[index] = (counts[index]||0)+1;
}
for(var i in counts){
var which = 1+parseInt(i);
var count = counts[i];
console.log("# of " + which +"'s: "+count);
}
https://jsfiddle.net/ga0fqpqn/
note: You shouldn't need the parseInt(i)... just +i should work but I think jsfiddle has a bug with it about it defaulting i to handle like a string.

You could store an additional array with the order of the numbers, which you only append to if the object doesn't yet contain the given number. Then once you're done counting, iterate through that array and output the number and the count from the lookup dictionary.
var chars = "1234576123452345".split("");
var order = [];
var hash = {};
chars.forEach(function(char) {
if (!hash[char]) {
hash[char] = 1;
order.push(char);
} else {
hash[char]++;
}
});
console.log(order.map(function(char) {
return char + hash[char];
}).join(""));
// "12233343537161"

Looping through a list of arrays to count the objects

I am been having trouble counting the number of objects in this array in javascript.
Below is the array of objects i try to count with my code.
<script>
var arr = [
{"gateways":["ccu1"],"manufacturer":["homematic"],"ir":["ir_no"],"ip":["ip_cam","ip_other"]},
{"gateways":["v3"],"manufacturer":["homematic"],"ir":["ir_no"],"ip":["ip_cam"]},
{"gateways":["v2","v3","v4","ccu2"],"manufacturer":["homematic","intertechno"],"ir":["ir_yes"],"ip":["ip_cam","ip_other"]},
{"gateways":["v2","ccu1","ccu2"],"manufacturer":["homematic"],"ir":["ir_yes"],"ip":["ip_cam","ip_other"]},
{"gateways":["gw_none"],"manufacturer":["homematic"],"ir":["ir_no"],"ip":["ip_cam"]},
{"gateways":["v3","ccu2"],"manufacturer":["homematic","fs20","intertechno","elro","Eltako Enocean"],"ir":["ir_yes"],"ip":["ip_cam","ip_other"]},
{"gateways":["v3","v4"],"manufacturer":["homematic"],"ir":["ir_no"],"ip":["ip_other"]},
{"gateways":["v3","v4"],"manufacturer":["homematic"],"ir":["ir_no"],"ip":["ip_other"]},
{"gateways":["v2"],"manufacturer":["intertechno"],"ir":["ir_yes"],"ip":["ip_other"]}
];
var counter = [];
for(var i=0; i<arr.length; i++) {
//console.log(arr[i]);
for(var index in arr[i]) {
console.log(index);
if(counter[index] === undefined) {
counter[index] = [];
}
}
}
console.log(counter);
</script>
I want the number of the objects to push into the empty array "counter" when you console log "counter" e.g.
gateways
ccu2 42
v4 70
v2 95
v3 91
v4plus 32
ccu1 16
gw_none 10
ip
ip_cam 4
ip_other 10
ip_none 4
ir
ir_yes 13
ir_no 18
manufacturer
homematic 24
fs20 59
intertechno 38
elro 63
homeeasy 40
somfy 11
I am new to programming and trying my hands on some few exercises like this one but i got stuck. I'm left with the codes to put the object counter to the empty array. I have tried but cannot let it work. I would appreciate any help and i hope my assignment makes sense and is understandable.

Change this:
if(counter[index] === undefined) {
counter[index] = [];
}
To this:
if(counter[index] === undefined) {
counter[index] = [];
}
counter[index].push( arr[i][index] );

Hope this code is helpful.
var arr = [
{"gateways":["ccu1"],"manufacturer":["homematic"],"ir":["ir_no"],"ip":["ip_cam","ip_other"]},
{"gateways":["v3"],"manufacturer":["homematic"],"ir":["ir_no"],"ip":["ip_cam"]},
{"gateways":["v2","v3","v4","ccu2"],"manufacturer":["homematic","intertechno"],"ir":["ir_yes"],"ip":["ip_cam","ip_other"]},
{"gateways":["v2","ccu1","ccu2"],"manufacturer":["homematic"],"ir":["ir_yes"],"ip":["ip_cam","ip_other"]},
{"gateways":["gw_none"],"manufacturer":["homematic"],"ir":["ir_no"],"ip":["ip_cam"]},
{"gateways":["v3","ccu2"],"manufacturer":["homematic","fs20","intertechno","elro","Eltako Enocean"],"ir":["ir_yes"],"ip":["ip_cam","ip_other"]},
{"gateways":["v3","v4"],"manufacturer":["homematic"],"ir":["ir_no"],"ip":["ip_other"]},
{"gateways":["v3","v4"],"manufacturer":["homematic"],"ir":["ir_no"],"ip":["ip_other"]},
{"gateways":["v2"],"manufacturer":["intertechno"],"ir":["ir_yes"],"ip":["ip_other"]}
];
var types = Object.keys(arr[0]); //Returns ["gateways","manufacturer","ir","ip"]
var counter = {};
types.forEach(function(type){
var values = [].concat.apply([], arr.map(function(d){ return d[type] })); // Find all values for each key like gateways
//Count occurrence of each value
var counts = {};
for(var i = 0; i< values.length; i++) {
var num = values[i];
counts[num] = counts[num] ? counts[num]+1 : 1;
}
counter[type] = counts;
});
alert(JSON.stringify(counter));
Output Obtained:
{
"gateways": {
"ccu1": 2,
"v3": 5,
"v2": 3,
"v4": 3,
"ccu2": 3,
"gw_none": 1
},
"manufacturer": {
"homematic": 8,
"intertechno": 3,
"fs20": 1,
"elro": 1,
"Eltako Enocean": 1
},
"ir": {
"ir_no": 5,
"ir_yes": 4
},
"ip": {
"ip_cam": 6,
"ip_other": 7
}
}

Thanks guys but i sat down and thought i got what i was missing;
//first we initialised counter
var counter = [];
//we then loop over the big array
for(var i=0; i<arr.length; i++) {
//we save then the single objects
var obj = arr[i];
// We then evaluate Object -> looping and count on each entry
for(var key in obj) {
//check whether there is already an entry for the respective
//index (gateways, Manufacturer etc)
if(counter[key] === undefined) {
counter[key] = [];
}
//Save the individual array of Object entries
var arr2 = obj[key];
//Looping and counting the array
for(var k=0; k<arr2.length; k++) {
var entry = arr2[k];
//Check whether there is already a counter for that
//item
if(counter[key][entry] === undefined) {
counter[key][entry] = 1;
} else {
counter[key][entry]++;
}
}
}
}
console.log(counter);

Combining results into one object

I'm looping through a set of inputs. I need to tally up the grouped totals. The inputs below to one of three categories.
How do I go about combining the values up relevant to three categories?
var compoundedArray = new Array();
holder.find(".dataset input").each(function(index) {
var val = $(this).val();
var dataType = $(this).data("type");
var localObj = {};
localObj[dataType] = val;
compoundedArray.push(localObj);
});
I have an object like this
[
{
"growth":30
},
{
"growth": 40
},
{
"other": 20
}
]
how do I loop through the object to produce something like
[
{
"growth": 70
},
{
"other": 20
}
]
if I looped over the initial array object
for (var i = 0; i < compoundedArray.length; i++) {
console.log(compoundedArray[i]);
}
how would I go about checking to ensure I don't have duplicates - and that I can tally up the results?
Ideally the resulting format may be the best
var array = [
"matching": 50,
"growth": 20
]

var array = [
"matching": 50,
"growth": 20
]
is not valid JS, but you can create an object of the form
var obj = {
"matching": 50,
"growth": 20
};
And that's pretty easy to do, just use an object from the very beginning:
var result = {};
holder.find(".dataset input").each(function(index) {
var val = +$(this).val(); // use unary plus to convert to number
var dataType = $(this).data("type");
result[dataType] = (result[dataType] || 0) + val;
});
Further reading material:
MDN - Working with Objects
Eloquent JavaScript - Data structures: Objects and Arrays

You can just use an object (not array) with unique keys.
var compoundedObj = {};
$(".dataset input", holder).each(function() {
var dataType = $(this).data("type");
if(!compoundedObj.hasOwnProperty(dataType)) {
compoundedObj[dataType] = 0;
}
compoundedObj[dataType] += parseInt($(this).val(), 10);
});
In this way you'll get an object like this:
{
"growth": 70,
"other": 20
}
Live demo

http://jsfiddle.net/GFwGU/
var original = [{"growth":30},{"growth": 40},{"other": 20}]
// object to sum all parts by key
var sums = {}
// loop through original object
for(var index in original){
// get reference to array value (target object)
var outer = original[index]
// loop through keys of target object
for(var key in outer){
// get a reference to the value
var value = outer[key]
// set or add to the value on the sums object
sums[key] = sums[key] ? sums[key] + value : value
}
}
// create the output array
var updated = []
// loop through all the summed keys
for(var key in sums){
// get reference to value
var value = sums[key]
// create empty object
var dummy = {}
// build object into desired format
dummy[key] = value
// push to output array
updated.push(dummy)
}
// check the results
alert(JSON.stringify( updated ))

var add=function (a,b){ a=a||0; b=b||0; return a+b};
var input=[ {growth:30},{growth:40},{other:20} ],output=[],temp={};
$.each(input,function(i,o){
var n;
for(i in o)
{n=i;break}
temp[n]=add(temp[n],o[n]);
});
$.each(temp,function(i,o){
var k={};
k[i]=o;
output.push(k)
});