Related
I have a nested array like below. There are about 100 de objects in the array. The de objects also have deg[0] array but most likely I will only have the first index. Now the trick is that the de are subset of deg. Which means each deg can have say 10 de. How can I retrieve the deg and there associated de and map it into a new array like:
newArray = [
deg1: [
{de1},
{de2}
],
deg2: [
{de1},
{de2}
]
]
Here is my nested array. I posted four but the list is over a 100.
{
"name": "Report",
"id": "2YYUEZ6I1r9",
"dse1": [
{
"de1": {
"name": "Number",
"id": "HjMOngg3kuy",
"de1-av": [
{
"value": "FHaQMPv9zc7",
"attribute": {
"id": "uwVkIP7PZDt"
}
},
{
"value": "something",
"attribute": {
"id": "FHaQMPv9zc7"
}
}
],
"deg1": [
{
"name": "TB",
"id": "2XJB1JO9qX8"
}
]
}
},
{
"de2": {
"name": "Number of",
"id": "a3dtGETTawy",
"de2-av": [
{
"value": "FHaQMPv9zc7",
"attribute": {
"id": "uwVkIP7PZDt"
}
},
{
"value": "something",
"attribute": {
"id": "FHaQMPv9zc7"
}
}
],
"deg1": [
{
"name": "Secondary",
"id": "w99RWzXHgtw"
}
]
}
},
{
"de1": {
"name": "Number of",
"id": "a3dtGETTawy",
"de1av": [
{
"value": "FHaQMPv9zc7",
"attribute": {
"id": "uwVkIP7PZDt"
}
},
{
"value": "something",
"attribute": {
"id": "FHaQMPv9zc7"
}
}
],
"deg2": [
{
"name": "Secondary",
"id": "w99RWzXHgtw"
}
]
}
},
{
"de2": {
"name": "Number of",
"id": "a3dtGETTawy",
"de2av": [
{
"value": "FHaQMPv9zc7",
"attribute": {
"id": "uwVkIP7PZDt"
}
},
{
"value": "something",
"attribute": {
"id": "FHaQMPv9zc7"
}
}
],
"deg2": [
{
"name": "Tertiary",
"id": "w99RWzXHgtw"
}
]
}
}
]
}
Group array of objects by property (this time a property to be matched by a reg exp) using Array.reduce.
Update: Ignoring missing keys.
var input={name:"Report",id:"2YYUEZ6I1r9",dse1:[{de1:{name:"Number",id:"HjMOngg3kuy","de1-av":[{value:"FHaQMPv9zc7",attribute:{id:"uwVkIP7PZDt"}},{value:"something",attribute:{id:"FHaQMPv9zc7"}}],deg1:[{name:"TB",id:"2XJB1JO9qX8"}]}},{de2:{name:"Number of",id:"a3dtGETTawy","de2-av":[{value:"FHaQMPv9zc7",attribute:{id:"uwVkIP7PZDt"}},{value:"something",attribute:{id:"FHaQMPv9zc7"}}],deg1:[{name:"Secondary",id:"w99RWzXHgtw"}]}},{de1:{name:"Number of",id:"a3dtGETTawy",de1av:[{value:"FHaQMPv9zc7",attribute:{id:"uwVkIP7PZDt"}},{value:"something",attribute:{id:"FHaQMPv9zc7"}}],deg2:[{name:"Secondary",id:"w99RWzXHgtw"}]}},{de2:{name:"Number of",id:"a3dtGETTawy",de2av:[{value:"FHaQMPv9zc7",attribute:{id:"uwVkIP7PZDt"}},{value:"something",attribute:{id:"FHaQMPv9zc7"}}],deg2:[{name:"Tertiary",id:"w99RWzXHgtw"}]}}]}
var reg = new RegExp("^de[0-9]+$");
var reg2 = new RegExp("^deg[0-9]+$");
let obj = input['dse1'].reduce(function(agg, item) {
// do your group by logic below this line
var key = Object.keys(item).find(function(key) {
return key.match(reg) ? key : null;
})
if (key) {
var key2 = Object.keys(item[key]).find(function(key) {
return key.match(reg2) ? key : null;
})
agg[key] = agg[key] || [];
if (key2) {
var to_push = {}
to_push[key2] = item[key][key2]
agg[key].push(to_push)
}
}
// do your group by logic above this line
return agg
}, {});
console.log(obj)
.as-console-wrapper {
max-height: 100% !important;
}
I'm stuck with something I thought would be easy. Let's say I have an object like this. I'm trying to insert in the div each name of the animal tagged and the number of times that tag is in types (for example, cat = 3, etc...)
var animals = '';
animals = {
"types": [
{
"id": "1",
"tags": ["cat"]
},
{
"id": "2",
"tags": ["dog"]
},
{
"id": "3",
"tags": ["cat", "bird", "dog"]
},
{
"id": "4",
"tags": []
},
{
"id": "5",
"tags": ["cat", "bird"]
}
]
}
for (var i = 0; i < animals.length; i++) {
var tags = animals[i].tags;
}
<div class="types">Number of animals:</div>
I'm a beginner with complex JSON objects, any help would be appreciated. It can be vanilla JS or Jquery.
Thanks!
Check out the snippet below, first loop iterates and counts each animal.
Second populates your div
var animals = '';
animals = {
"types": [{
"id": "1",
"tags": ["cat"]
},
{
"id": "2",
"tags": ["dog"]
},
{
"id": "3",
"tags": ["cat", "bird", "dog"]
},
{
"id": "4",
"tags": []
},
{
"id": "5",
"tags": ["cat", "bird"]
}
]
}
var tags = {};
// Iterate over all your items
animals.types.forEach(function(type) {
// Iterate over all the animals in the array
type.tags.forEach(function(tag) {
if (tag in tags) {
// If animal is present, increment the count
tags[tag] = tags[tag] + 1;
} else {
// If animal is not present, add the entry
tags[tag] = 1;
}
})
})
// Iterate over all the animals and add it to the div
for (var animal in tags) {
if (tags.hasOwnProperty(animal)) {
document.getElementsByClassName('types')[0].innerHTML += ' ' + animal + ' ' + tags[animal];
}
}
<div class="types">Number of animals:</div>
You can do like this by using map() method :
var animals = {
"types": [{
"id": "1",
"tags": ["cat"]
},
{
"id": "2",
"tags": ["dog"]
},
{
"id": "3",
"tags": ["cat", "bird", "dog"]
},
{
"id": "4",
"tags": []
},
{
"id": "5",
"tags": ["cat", "bird"]
}
]
};
var count = {};
animals.types.map(function (arr, i) {
arr.tags.map(function (tag, k) {
count[tag] = (count[tag] || 0) + 1;
});
});
console.log(count);
If you use reduce & destrucuring it becomes one liner:
var animals = {
"types": [{
"id": "1",
"tags": ["cat"]
},
{
"id": "2",
"tags": ["dog"]
},
{
"id": "3",
"tags": ["cat", "bird", "dog"]
},
{
"id": "4",
"tags": []
},
{
"id": "5",
"tags": ["cat", "bird"]
}
]
}
console.log(
animals.types.reduce((r,{tags}) => tags.map(tag => r[tag] = (r[tag] || 0) + 1) && r, {})
)
Try this simple way:
var animals = { "types": [ { "id": "1", "tags": ["cat"] }, { "id": "2", "tags": ["dog"] }, { "id": "3", "tags": ["cat", "bird", "dog"] }, { "id": "4", "tags": [] }, { "id": "5", "tags": ["cat", "bird"] } ] }
var finalRes={};
animals.types.map(function(o, i){
o.tags.map(function(p, j){
finalRes[p]=(finalRes[p]||0)+1;
});
});
console.log(finalRes);
Result:
{ cat: 3, dog: 2, bird: 2 }
Sorry, I am typing with mobile phone, slow but correct!
Flatten all tags into single array
Count each tag
Handle tag count as you need
const animals = {
"types": [
{
"id": "1",
"tags": ["cat"]
},
{
"id": "2",
"tags": ["dog"]
},
{
"id": "3",
"tags": ["cat", "bird", "dog"]
},
{
"id": "4",
"tags": []
},
{
"id": "5",
"tags": ["cat", "bird"]
},
],
};
// Flatten all tags into single array
var allTags = [].concat(
...animals.types.map(
(type) => type.tags
)
);
// Count each tag
const tagsCount = {};
allTags.forEach(
(tag) => tagsCount[tag] = tagsCount[tag] ? tagsCount[tag] + 1 : 1
)
// Handle tag count as you need
const app = document.querySelector('#app');
app.innerHTML = Object.keys(tagsCount).map((key) => {
return `<p>${key}: ${tagsCount[key]}</p>`
}).join('');
<h1>Number of Animal Types</h1>
<div id="app"></div>
Basic javascript usage.
// var animals = ''; // not needed
var animals = {
"types": [{
"id": "1",
"tags": ["cat"]
},
{
"id": "2",
"tags": ["dog"]
},
{
"id": "3",
"tags": ["cat", "bird", "dog"]
},
{
"id": "4",
"tags": []
},
{
"id": "5",
"tags": ["cat", "bird"]
}
]
};
var counts = {};
for (var i = 0; i < animals.types.length; i++) { // types is a key in animals object, animals is not an array
var tags = animals.types[i].tags;
if (tags.length > 0) {
for (var j = 0; j < tags.length; j++) {
var tag = tags[j];
if (typeof counts[tag] === 'undefined') {
counts[tag] = 0;
}
counts[tag]++;
}
}
}
console.log(counts);
You could create a hash map for all the tags and increment the count whenever you encounter that tag in that types.tags array
Then loop through the object and append that into your HTML Element
var animals = '';
animals = {
"types": [
{
"id": "1",
"tags": ["cat"]
},
{
"id": "2",
"tags": ["dog"]
},
{
"id": "3",
"tags": ["cat", "bird", "dog"]
},
{
"id": "4",
"tags": []
},
{
"id": "5",
"tags": ["cat", "bird"]
}
]
}
let types = animals.types;
var counts = {};
for (var i = 0; i < types.length; i++) {
types[i].tags.forEach((x) => {
counts[x] = (counts[x] || 0)+1;
});
}
console.log(counts);
<div class="types">Number of animals:</div>
I have below dynamic nested JSON object arrays and I wanted to get the desired output with JavaScript grouped by id from both.
First Array:
[
{
"id": "11",
"name": "emp1",
"location": [
{ "name": "abc", "id": "lc1" }
]
},
{
"id": "11",
"name": "emp2",
"location": [
{ "name": "abc", "id": "lc1" },
]
},
{
"id": "22",
"name": "emp3",
"location": [
{ "name": "xyz", "id": "lc2" }
]
}
]
Second array like below.
[
{
"name": "sub1",
"id": "11"
...
},
{
"name": "sub1.1",
"id": "11"
...
},
{
"name": "sub2",
"id": "22"
...
}
]
Desired Output:
[
{
"id": "11",
"first": [{"name": "emp1"},
{"name": "emp2"}],
"second": [{"name": "sub1"},{"name": "sub1.1"}],
"location": [{"name": "abc"}]
},
{
"id": "22",
"first": [{"name": "emp3"}],
"second": [{"name": "sub2"}],
"location": [{"name": "xyz"}]
}
]
How to get the desired output like above using javascript/angularjs?
I would do it using the amazing Array#reduce function.
Note that I have named your first array as a1, second as a2 and result as res.
a1.reduce(function(arr, obj) {
var existing = arr.filter(function(res) {
return res.id === obj.id
})[0]
if (existing) {
existing.first.push({
name: obj.name
})
} else {
var second = a2.filter(function(res) {
return res.id === obj.id
})
var secondObj = second.length ? second.map(function(sec) {
return {
name: sec.name
};
}) : []
arr.push({
id: obj.id,
first: [{
name: obj.name
}],
second: secondObj,
location: obj.location
})
}
return arr;
}, [])
Here's the working snippet. Take a look!
var a1 = [{
"id": "11",
"name": "emp1",
"location": [{
"name": "abc",
"id": "lc1"
}]
},
{
"id": "11",
"name": "emp2",
"location": [{
"name": "abc",
"id": "lc1"
}]
},
{
"id": "22",
"name": "emp3",
"location": [{
"name": "xyz",
"id": "lc2"
}]
}
]
var a2 = [{
"name": "sub1",
"id": "11"
}, {
"name": "sub1.1",
"id": "11"
},
{
"name": "sub2",
"id": "22"
}
]
var res = a1.reduce(function(arr, obj) {
var existing = arr.filter(function(res) {
return res.id === obj.id
})[0]
if (existing) {
existing.first.push({
name: obj.name
})
} else {
var second = a2.filter(function(res) {
return res.id === obj.id
})
var secondObj = second.length ? second.map(function(sec) {
return {
name: sec.name
};
}) : []
arr.push({
id: obj.id,
first: [{
name: obj.name
}],
second: secondObj,
location: obj.location
})
}
return arr;
}, [])
console.log(res)
.as-console-wrapper {
max-height: 100% !important;
top: 0;
}
var red1 = [{
"id": "11",
"name": "emp1",
"location": [{
"name": "abc",
"id": "lc1"
}]
},
{
"id": "11",
"name": "emp2",
"location": [{
"name": "abc",
"id": "lc1"
}]
},
{
"id": "22",
"name": "emp3",
"location": [{
"name": "xyz",
"id": "lc2"
}]
}
]
var b = [{
"name": "sub1",
"id": "11"
},
{
"name": "sub2",
"id": "22"
}
]
var identication = {}
var result = []
red1.forEach(function(val) {
if (val['id'] in identication) {
var t = {}
t['name'] = val['name']
result[identication[val['id']]]['first'].push(t)
} else {
var t = {}
t['name'] = val['name']
val['first'] = []
val['first'].push(t)
delete val['name']
var identity = result.push(val)
identication[val['id']] = identity - 1;
}
})
b.forEach(function(d) {
if (d['id'] in identication) {
var t = {
'name': d['name']
}
if (!('second' in result[identication[d['id']]])) {
result[identication[d['id']]]['second'] = []
}
result[identication[d['id']]]['second'].push(t)
} else {
var t = {}
for (key in d) {
if (key == 'name')
continue
t[key] = d[key]
}
t['second'] = [{
'name': d['name']
}]
var identity = result.push(t)
identication[d['id']] = identity - 1;
}
})
console.log(result)
I want to build an new JSON from existing one. The source has sections and rubrics that I no longer need for a listing. The new object called 'items' should have an array of the items.
The final JSON should be sorted by attribute 'name' and look like
{
"items": [
{
"id": 10000006,
"name": "Boah"
},
{
"id": 10000013,
"name": "Gut"
},
{
"id": 10000003,
"name": "Ipsum"
},
{
"id": 10000001,
"name": "Lorem"
},
{
"id": 10000005,
"name": "Lorum"
},
{
"id": 10000004,
"name": "Name"
},
{
"id": 10000002,
"name": "Stet"
}
]
}
For building the new JSON I get this source:
{
"sections": [
{
"name": "FooBar",
"rubrics": [
{
"name": "Foo",
"items": [
{
"id": 10000001,
"name": "Lorem"
},
{
"id": 10000002,
"name": "Stet"
},
{
"id": 10000003,
"name": "Ipsum"
}
]
},
{
"name": "Bar",
"items": [
{
"id": 10000004,
"name": "Name"
},
{
"id": 10000005,
"name": "Lorum"
},
{
"id": 10000006,
"name": "Boah"
}
]
}
]
},
{
"name": "BlahBloob",
"rubrics": [
{
"name": "Bla",
"items": [
{
"id": 10000013,
"name": "Gut"
}
]
},
{
"name": "Bloob",
"items": [
{
"id": 10000014,
"name": "Name"
},
{
"id": 10000015,
"name": "Lorem"
}
]
}
]
}
]
}
What do you think? How can I do this with plain JavaScript or maybe TypeScript?
Thanks for reading and have time for my question. And thanks for reply in advance.
Here you go. You just need to iterate over each rubric of each section of your source to get the items. At the end, sort your list of items by items, and you're done.
This example uses ES6 syntax, but it's easy to convert it to ES5 if needed.
function extractItems(source) {
const items = [];
for (const section of source.sections) {
for (const rubric of section.rubrics) {
items.push(...rubric.items);
}
}
items.sort((a, b) => a.name.localeCompare(b.name));
return { items };
}
A more functional approach use map and reduce to pick the rubrics and merge them.
data.sections
.map(section => section.rubrics) // get rubrics
.reduce((a, b) => a.concat(b)) // merge rubrics
.map(rubric => rubric.items) // get items from each rubric
.reduce((a, b) => a.concat(b)) // merge items
.sort((a, b) => a.name.localeCompare(b.name)); // sort
function(oldObj) {
var newObj = {
"items": []
};
oldObj.sections.forEach(function(section) {
section.rubrics.forEach(function(rubric) {
rubric.items.forEach(function(item) {
newObj.items.push(item);
});
});
});
newObj.items = newObj.items.sort(function(a, b) {
if (a.name < b.name) { return -1; }
if (a.name > b.name) { return 1; }
return 0;
});
return newObj;
}
And simply use JSON.parse() and JSON.stringify() to convert JSON to and from objects.
It might help you
var data ={
"sections": [
{
"name": "FooBar",
"rubrics": [{"name": "Foo", "items": [{"id": 10000001,"name": "Lorem"}, {"id": 10000002,"name": "Stet"}, {"id": 10000003,"name": "Ipsum"}]
}, {
"name": "Bar",
"items": [{
"id": 10000004,
"name": "Name"
}, {
"id": 10000005,
"name": "Lorum"
}, {
"id": 10000006,
"name": "Boah"
}]
}]
}, {
"name": "BlahBloob",
"rubrics": [{
"name": "Bla",
"items": [{
"id": 10000013,
"name": "Gut"
}]
}, {
"name": "Bloob",
"items": [{
"id": 10000014,
"name": "Name"
}, {
"id": 10000015,
"name": "Lorem"
}]
}]
}]
};
var itemObj = {};
var itemArr = [];
var sections = data.sections;
for(var i=0;i<sections.length;i++)
{
for(var j=0;j<sections[i].rubrics.length;j++){
for(var k=0;k<sections[i].rubrics[j].items.length;k++){
var itemObj;
itemObj['id'] = sections[i].rubrics[j].items[k].id;
itemObj['name'] = sections[i].rubrics[j].items[k].name;
itemArr.push(itemObj);
}
}
}
var finalObj = {"items":itemArr};
console.log(finalObj);
JSFiddle
How can we change the structure of the below data object using JavaScript. Needs to categorize all the names under the std. Thanks in advance
[
{
"name": "Rohan",
"std": "3"
},
{
"name": "Jack",
"std": "2"
},
{
"name": "Peter",
"std": "2"
}
]
to
[
{
"std": "2",
"details": [
{
"name": "Jack"
},
{
"name": "Peter"
}
]
},
{
"std": "3",
"details": [
{
"name": "Rohan"
}
]
}
]
The solution using Array.forEach, Array.map and Object.keys functions:
var arr = [{"name": "Rohan", "std": "3"}, { "name": "Jack", "std": "2" }, { "name": "Peter", "std": "2" }],
grouped = {}, result;
arr.forEach(function(obj){
var std = obj['std'];
if (this[std]) {
this[std]['details'].push({'name' : obj['name']});
} else {
this[std] = {'std' : std, 'details' : [{'name' : obj['name']}]};
}
}, grouped);
result = Object.keys(grouped).map((k) => grouped[k]);
console.log(JSON.stringify(result, 0, 4));
The output:
[
{
"std": "2",
"details": [
{
"name": "Jack"
},
{
"name": "Peter"
}
]
},
{
"std": "3",
"details": [
{
"name": "Rohan"
}
]
}
]
You can use reduce() method here
var data = [{
"name": "Rohan",
"std": "3"
}, {
"name": "Jack",
"std": "2"
}, {
"name": "Peter",
"std": "2"
}],
res = [],
kmap = {};
res = data.reduce(function(a, b) {
// check std value already in array using kmap object
if (kmap[b.std]) {
// if already exist then push name attribute in the details
a[kmap[b.std] - 1].details.push({
'name': b.name
});
} else {
// in else case push the new object
a.push({
'std': b.std,
'details': [{
'name': b.name
}]
});
kmap[b.std] = a.length; // storing the (index + 1) value to avoid 0 in if condition
}
return a;
}, []);
console.log(res);
For older browsers check polyfill option for reduce method.
Problems like this are good candidates for recursion. Here is one possible recursive solution. You can make it much prettier using a functional programming framework such as underscore.js.
var objs = [
{
"name": "Rohan",
"std": "3"
},
{
"name": "Jack",
"std": "2"
},
{
"name": "Peter",
"std": "2"
}
];
function categorize(objs) {
if (objs.length === 0) {
return [];
} else {
var first = objs.shift();
var categorized = categorize(objs);
for(var i = 0; i < categorized.length; i++) {
if (categorized[i].std === first.std) {
categorized[i].details.push({name: first.name});
break;
}
}
if(i === categorized.length) {
categorized.push({std: first.std, details: [{name: first.name}]});
}
return categorized;
}
}
var res = categorize(objs);
console.log(res);
If you're using lodash (I know the question didn't ask this and it's going to be slower, but it may be useful to someone :))
var data = [
{ "name": "Rohan", "std": "3" },
{ "name": "Jack", "std": "2" },
{ "name": "Peter", "std": "2" }
];
var grouped = _.chain(data)
.groupBy('std')
.map(function (people, std) {
return {
std: std,
details: _.map(people, function(person) {
return { name: person.name };
})
}
}).value();