I have the following json array:
array 1:
fruits1 = [{"fruit":"banana","amount":"2","color":"yellow"},{"fruit":"apple","amount":"5","color":"red"},{"fruit":"kiwi","amount":"1","color":"green"}]
array 2:
fruits2 = [{"fruit":"banana","sold":"1","stock":"3"},{"fruit":"apple","sold":"3","stock":"5"},{"fruit":"kiwi","sold":"2","stock":"3"}]
I would like to get just one array which has the results merged according to the fruits value like this:
fruits = [{"fruit":"banana","amount":"2","color":"yellow","sold":"1","stock":"3"},{"fruit":"apple","amount":"5","color":"red","sold":"3","stock":"5"},{"fruit":"kiwi","amount":"1","color":"green","sold":"2","stock":"3"}]
I need to do something like
foreach item.fruit where fruit = fruit from initial array
fruits.push item
Any idea?
Try this logic:
function merge_options(obj1,obj2){
var obj3 = {};
for (var attrname in obj1) { obj3[attrname] = obj1[attrname]; }
for (var attrname in obj2) { obj3[attrname] = obj2[attrname]; }
return obj3;
}
var obj1 = [];
for (var i = 0; i < fruits1.length ; i++) {
obj1[fruits1[i].fruit] = fruits1[i];
}
var obj2 = [];
for (var i = 0; i < fruits2.length ; i++) {
obj2[fruits2[i].fruit] = fruits2[i];
}
var fruits = []
for (var key in obj1) {
fruits.push(merge_options(obj1[key],obj2[key]));
}
console.log(fruits);
You can do something like this with javascript
// create a hash like {fruit_name -> object}
f1 = {};
fruits1.forEach(function(p) {
f1[p.fruit] = p;
});
// merge second array into above hash on fruit_name
fruits2.forEach(function(p) {
for (var a in p) { f1[p.fruit][a] = p[a];}
});
//fruits1 will now contain result;
//if you don't want to spoil fruit1 array, clone p inside 'fruits1.forEach' above before assigning it to 'f1[p.fruit]'. And at the end, create a new array out of f1
Here's a generic way that works with your data:
function joinObjects(initial, other, predicate, valueSelector) {
if(typeof(predicate) !== 'function') throw 'predicate must be a function';
if(typeof(valueSelector) !== 'function') throw 'valueSelector must be a function';
// make a clone of the original object so its not modified
var clone = jQuery.extend(true, {}, initial);
// iterate over the initial and other collections
for(var cloneKey in clone) {
if (!clone.hasOwnProperty(cloneKey)) continue;
for(var otherKey in other) {
if (!other.hasOwnProperty(otherKey)) continue;
// if the predicate is truthy, get the values
if (predicate(clone[cloneKey], other[otherKey])) {
// pull only the values you want to merge
var values = valueSelector(other[otherKey]);
// iterate over the values add them to the cloned initial object
for(var valueKey in values) {
if (values.hasOwnProperty(valueKey)) {
clone[cloneKey][valueKey] = values[valueKey];
}
}
}
}
}
return clone;
}
var fruits1 = [{"fruit":"banana","amount":"2","color":"yellow"},{"fruit":"apple","amount":"5","color":"red"},{"fruit":"kiwi","amount":"1","color":"green"}];
var fruits2 = [{"fruit":"banana","sold":"1","stock":"3"},{"fruit":"apple","sold":"3","stock":"5"},{"fruit":"kiwi","sold":"2","stock":"3"}];
var finalFruits = joinObjects(fruits1, fruits2,
function(left, right) { return left.fruit == right.fruit },
function(other) {
return {
sold: other.sold,
stock: other.stock
};
});
console.log(finalFruits);
Related
I implemented an aggregation function but the only problem I have now is that I lost my key: value format e.g [{name:"Apples",val:8},{name:"Banana",val: 9}].
function agrregate(a){
var targetObj = {};
var result;
var b = JSON.parse(JSON.stringify(a));
var trees= b.length;
if(!trees){
trees = 0
}
for (var i = 0; i < trees; i++) {
if (!targetObj.hasOwnProperty(b[i].key)) {
targetObj[b[i].key] = 0;
}
targetObj[b[i].key] += b[i].val;
}
result = JSON.stringify(targetObj);
return result;
}
This is the result i get when agrregate function completes.
{"Apple":8,"Banana":9}
Instead of
{name:"Apple", val:8}, {name:"Banana", val:9}
Use a reducer to aggregate. You don't need to do stuff with JSON stringify/parse.
To get back to an array of objects, you use map and Object.keys
var test = [{name:"Apples",val:5},{name:"Banana",val: 9},{name:"Apples",val:3}]
var aggregate = function(arr) {
return arr.reduce(function(result, obj) { // Create one object (result)
result[obj.name] = (result[obj.name] || 0) + obj.val; // Add a new key/or increase
return result // Return the object
}, {});
};
var wrap = function(obj) {
return Object.keys(obj) // Create an array of keys
.map(function(key) {
return { // Specify the format
name: key,
val: obj[key]
};
});
};
console.log(aggregate(test));
console.log(wrap(aggregate(test)));
I have one object that I had to take apart into two arrays to handle properly.
It looked like this:
{
city:"stuttgart",
street:"randomstreet",
...
}
Since it needs to fit a certain directive I had to convert it to:
[
{key:"city", value:"stuttgart"}
{key:"street", value:"randomstreet"},
...
]
for this I first used
var mapFromObjectWithIndex = function (array) {
return $.map(array, function(value, index) {
return [value];
});
};
var mapFromObjectWithValue = function (array) {
return $.map(array, function(value, index) {
return [index];
});
});
to create two arrays, one containing the old key, the other one is holding the old value. Then I created another, two dimensional array map them into a single array doing this
var mapToArray = function (arrayValue, arrayIndex) {
var tableData = [];
for (var i = 0; i<arrayIndex.length; i++){
tableData[i] = {key:arrayIndex[i] , value:arrayValue[i]};
}
return tableData;
};
(maybe I have already messed up by here, can this be done any easier?)
Now, I use the array (tableData) to display the data in a form. The value fields can be edited. In the end, I want to convert the array (tableData) to its original. (see first object)
Please note, that the original object doesn't only contain strings as values, but can also contain objects as well.
I think conversion can be definitely easier:
var obj = {
city:"stuttgart",
street:"randomstreet",
};
var tableData = Object.keys(obj).map(k => {return {key: k, value: obj[k]}});
console.log(tableData);
var dataBack = {};
tableData.forEach(o => dataBack[o.key] = o.value);
console.log(dataBack);
What do you want to do with objects? Do you want to expand them as well? If yes you can do something like this (and it works with nested objects as well):
var obj = {
city:"stuttgart",
street:"randomstreet",
obj: {a: 'a', b: 'b'},
subObject: {aha: {z: 'z', y: 'y'}}
};
function trasformToTableData(obj) {
if (typeof obj !== 'object') return obj;
return Object.keys(obj).map(k => {return {key: k, value: trasformToTableData(obj[k])}});
}
var tableData = trasformToTableData(obj);
console.log(tableData);
function transformBack(obj) {
if (Array.isArray(obj)) {
var support ={};
for (let i = 0; i < obj.length; i++) {
support[obj[i].key] = transformBack(obj[i].value)
}
return support;
}
return obj;
}
var dataBack = {};
tableData.forEach(o => dataBack[o.key] = transformBack(o.value));
console.log(dataBack);
Let's have some fun and turn our object into iterable to do the job as follows;
var input = {city:"stuttgart", street:"randomstreet", number: "42"};
output = [];
input[Symbol.iterator] = function*(){
var ok = Object.keys(this),
i = 0;
while (i < ok.length) yield {key : ok[i], value: this[ok[i++]]};
};
output = [...input];
console.log(output);
This function will map your object to an array when you call objVar.mapToArray(), by using Object.keys() and .map()
Object.prototype.mapToArray = function() {
return Object.keys(this).map(function(v) {
return { key: v, value: this[v] };
}.bind(this));
}
I would do something like this:
var dataObj = {
city:"stuttgart",
street:"randomstreet",
};
function toKeyValue(obj) {
var arr = [];
for (var key in obj) {
if(obj.hasOwnProperty(key)) {
arr.push({'key': key, 'value': obj[key]});
}
}
return arr;
}
var arrayKeyValue = toKeyValue(dataObj);
console.log(arrayKeyValue);
I am receiving data in object form. that object contains properties in which three keys are holding array values. I want to push concat those three array into one master Array. But should be in preferred sequence. Like
var obj = {'type':['a','b'],'power':[500,700],'make':['2012','2015']}
oneArray(obj,'make','type','power')
The master Array should have first 'make', 'type' and then 'power' keys Array from object. Right now it is coming in order which is given in obj
Fidde
var obj = {'type':['a','b'],'power':[500,700],'make':['2012','2015']}
var oneArray = function (obj,first,second,third){
var newObj = obj;
var list = [];
for(var key in newObj){
if (newObj[key] instanceof Array) {
if (!list) {
list = newObj[key];
}
else {
list = list.concat(newObj[key]);
}
}
}
newObj['all'] = list;
return newObj
}
console.log(oneArray(obj,'make','type','power'))
I'm not sure I have understood your question, but try this...
This onArray() function takes parameters that indicating priorities in orderly manner but first parameter.
var obj = {'type':['a','b'],'power':[500,700],'make':['2012','2015']}
var oneArray = function(obj) {
var newObj = obj;
var list = [];
var priorityList = arguments;
for( var i = 1 ; i < priorityList.length ; i++ ) {
if( newObj[ priorityList[i] ] instanceof Array ) {
for( var key in newObj[ priorityList[i] ] ) {
list.push( newObj[ priorityList[i] ][ key ] );
}
}
}
newObj['all'] = list;
return newObj;
}
console.log(oneArray(obj,'make','type','power'));
I have an array:
["car1-coupe", "car2-convertible", "car2-hatchback", "car2-estate", "car3-hatchback", "car3-estate"]
The array can have different sets of cars, and I want to turn it into something like this:
[{
car1: ["car1-coupe"]
},{
car2: ["car2-convertible", "car2-hatchback", "car2-estate"]
},{
car3: ["car3-hatchback", "car3-estate"]
}]
How can I do this in JavaScript or Underscore?
So, assuming an array like this:
var a = ["car1-coupe", "car2-convertible", "car2-hatchback", "car2-estate", "car3-hatchback", "car3-estate"];
You can do this:
var b = a.reduce(function(prev, curr){
var car = curr.split('-')[0]; // "get" the current car
prev[car] = prev[car] || []; // Initialize the array for the current car, if necessary.
prev[car].push(curr); // Add the current item to the array.
return prev;
}, {});
This will return the following object:
{
car1: ["car1-coupe"],
car2: ["car2-convertible", "car2-hatchback", "car2-estate"],
car3: ["car3-hatchback", "car3-estate"]
}
var array = ["car1-coupe", "car2-convertible", "car2-hatchback", "car2-estate", "car3-hatchback", "car3-estate"];
var result = {};
for (var i = 0; i < array.length; i++) {
var key = array[i].split('-')[0]; // The car we're interested in
if (result[key]) { // Check if this car has already been initialized
result[key].push(array[i]); //add this model to the list
} else {
result[key] = [array[i]]; // initialize the array with the first value
}
}
console.log(result);
/*will return :
{
car1: ["car1-coupe"],
car2: ["car2-convertible", "car2-hatchback", "car2-estate"],
car3: ["car3-hatchback", "car3-estate"]
}
*/
var myObj = {}, myArr = [];
for( var i = 0; i < arr.length; i+=1) {
var key = arr[i].split("-")[0];
myObj = {};
myObj[key] = [];
for( var j = i; j < arr.length; j+=1 ) {
if( key === arr[j].split("-")[0])
myObj[key].push(arr[j]);
}
myArr.push(myObj);
}
I think this can be done simply with this way. One loop to get the key and another inner loop to get all values of this key.
I have this array:
["userconfig", "general", "name"]
and I would like it to look like this
data_structure["userconfig"]["general"]["name"]
I have tried this function:
inputID = "userconfig-general-name"
function GetDataByID(inputID){
var position = '';
for (var i = 0; i < inputID.length; i++) {
var hirarchy = inputID[i].split('-');
for (var index = 0; index < hirarchy.length; index++) {
position += '["'+ hirarchy[index] +'"]';
}
}
return data_structure[position];
}
while hirarchy is the array. I get the [position] as a string which is not working well.
how can I make a js function which builds the object path dynamically by an array?
var arr = ["userconfig", "general", "name"];
var dataStructure = arr.reduceRight(function (value, key) {
var obj = {};
obj[key] = value;
return obj;
}, 'myVal');
Ends up as:
{ userconfig : { general : { name : 'myVal' } } }
Note that you may need a polyfill for the reduceRight method: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/ReduceRight
The below function will take an object to modify and an array filled with the properties needed:
function objPath(obj,path){
path.forEach(function(item){
obj[item] = {};
obj = obj[item];
});
}
var myobj = {};
objPath(myobj,["test","test2","test3"]);
console.log(myobj);
//outputs
Object {test: Object}
test: Object
test2: Object
test3: Object
The function loops over the array creating the new object property as a new object. It then puts a reference to the new object into obj so that the next property on the new object can be made.
JSFiddle
Recursive function
var array = ["userconfig", "general", "name"];
function toAssociative(array) {
var index = array.shift();
var next = null;
if (array.length > 0) {
next = toAssociative(array);
}
var result = new Array();
result[index] = next;
return result;
}