I have the following data structure:
const data = [
{
name: 'ABC',
salesData: [
{
timestamp: '2017-09-01',
value: 10
},
{
timestamp: '2017-09-02',
value: 2
}
]
},
{
name: 'DEF',
salesData: [
{
timestamp: '2017-09-01',
value: 8
},
{
timestamp: '2017-09-02',
value: 3
}
]
}
];
I would like to transform this to:
[
{
name: 'ABC',
'2017-09-01': 10,
'2017-09-02': 2
},
{
name: 'CDE',
'2017-09-01': 8,
'2017-09-02': 3
}
]
I'm trying to use Underscore's Chain and Map which I'm getting confused. So far I have the following, not sure how do I write the convertedSalesData to transform as per the need:
_.map(data, function(item) {
let name = item.name;
let salesData = item.salesData;
let convertedSalesData = ?
})
With ES6 you can use spread syntax ... to get this result.
const data = [{"name":"ABC","salesData":[{"timestamp":"2017-09-01","value":10},{"timestamp":"2017-09-02","value":2}]},{"name":"DEF","salesData":[{"timestamp":"2017-09-01","value":8},{"timestamp":"2017-09-02","value":3}]}]
var result = data.map(function({name, salesData}) {
return {name, ...Object.assign({}, ...salesData.map(({timestamp, value}) => ({[timestamp]: value})))}
})
console.log(result)
const data = [{
name: 'ABC',
salesData: [{
timestamp: '2017-09-01',
value: 10
},
{
timestamp: '2017-09-02',
value: 2
}
]
},
{
name: 'DEF',
salesData: [{
timestamp: '2017-09-01',
value: 8
},
{
timestamp: '2017-09-02',
value: 3
}
]
}
];
var res = data.map(function(a) {
var obj = {
name: a.name
};
a.salesData.forEach(function(x) {
obj[x.timestamp] = x.value;
})
return obj;
})
console.log(res);
Similar to #Nenad Vracar. I perfer to use 'reduce':
data.map(({ name, salesData }) => ({
name,
...salesData.reduce(
(record, { timestamp, value }) => {
record[timestamp] = value
return record
},
Object.create(null)
)
}))
Related
I have data like this
finalValue [
{ _id: { _id: 'OUTCOME_APPROUVED' }, count: 1 },
{ _id: { _id: 'OUTCOME_SWITCH_INTERFACE' }, count: 5 }
]
I want to spread the inner object and change the keys to name and value to make final value looks like this
finalValue [
{ name: 'OUTCOME_APPROUVED' , value: 1 },
{ name: 'OUTCOME_SWITCH_INTERFACE' , value: 5 }
]
try this :
var finalValue = [
{ _id: { _id: 'OUTCOME_APPROUVED' }, count: 1 },
{ _id: { _id: 'OUTCOME_SWITCH_INTERFACE' }, count: 5 }
]
var newValue = finalValue.map(({_id:{_id},count}) => {
return {name:_id , value:count}
})
console.log(newValue)
[JS]
You could use map instead of spreading, and not sure about how you could spread it to format it the way you want.
const inputValue = [ { _id: { _id: 'OUTCOME_APPROUVED' }, count: 1 },
{ _id: { _id: 'OUTCOME_SWITCH_INTERFACE' }, count: 5 }]
const computedValue = inputValue.map((data) => {
return { name: data._id._id, value: data.count };
});
So I have a data like this
const carts = [
{
name: 'Voucher A',
participants: [
{
date: 112
},
{
date: 112
}
],
supplierName: 'ABC',
ticketDescription: 'Description of',
...data
},
{
name: 'Voucher B',
participants: [
{
date: 111
},
{
date: 112
}
],
supplierName: 'ABC',
ticketDescription: 'Description of',
...data
}
]
And I want to group it based on the date (if it has same date). So for data above, the expected result will be
expected = [
{
name: 'Voucher A',
date: 1,
count: 1,
supplierName: 'ABC',
ticketDescription: 'Description of',
...data
},
{
name: 'Voucher A',
date: 2,
count: 1,
supplierName: 'ABC',
ticketDescription: 'Description of',
...data
}
]
Because it has different date. But if it has same date, the expected result will be
expected = [
{
name: 'Voucher A',
date: 1,
count: 2,
supplierName: 'ABC',
ticketDescription: 'Description of',
...data
}
]
I was trying to use reduce to group it but it did not give the structure I want
carts.forEach(cart => {
cart.participants.reduce((acc, obj) => {
acc[obj.date] = [...acc[obj.date] || [], obj]
return acc
}, {})
})
To organize the data, I think you need two associations to group by: the name and the dates and their counts for that name:
const carts = [
{
name: 'Voucher A',
participants: [
{
date: 1
},
{
date: 2
}
]
}
];
const groupedByNames = {};
for (const { name, participants } of carts) {
if (!groupedByNames[name]) groupedByNames[name] = {};
for (const { date } of participants) {
groupedByNames[name][date] = (groupedByNames[name][date] || 0) + 1;
}
}
const output = Object.entries(groupedByNames).flatMap(
([name, dateCounts]) => Object.entries(dateCounts).map(
([date, count]) => ({ name, date: Number(date), count })
)
);
console.log(output);
If you want use, just plain for loops, you can try this solution. It looks simple and elegant 😜😜
const carts = [
{
name: 'Voucher A',
participants: [
{
date: 1
},
{
date: 1
},
{
date: 2
}
]
},
{
name: 'Voucher B',
participants: [
{
date: 1
},
{
date: 2
},
{
date: 2
}
]
}
]
const finalOutput = []
for (const cart of carts) {
for (const participant of cart.participants) {
const res = finalOutput.find(e => e.name === cart.name && e.date === participant.date)
if (res) {
res.count += 1
} else {
finalOutput.push({ name: cart.name, date: participant.date, count: 1 })
}
}
}
console.log(finalOutput)
Use forEach and destructuring
const process = ({ participants, name }) => {
const res = {};
participants.forEach(({ date }) => {
res[date] ??= { name, count: 0, date };
res[date].count += 1;
});
return Object.values(res);
};
const carts = [
{
name: "Voucher A",
participants: [
{
date: 1,
},
{
date: 2,
},
],
},
];
console.log(carts.flatMap(process));
const carts2 = [
{
name: "Voucher A",
participants: [
{
date: 1,
},
{
date: 1,
},
],
},
];
console.log(carts2.flatMap(process));
I have an array
const a = [
{ name: "read-web-courses" },
{ name: "example" },
{ name: "t_gql" },
{ name: "ddddd" },
];
I am trying it to reduce it to the below given output , However I am stuck
Output
{0:"read-web-courses",1:"example",2:"t_gql",3:"ddddd"}
You could map the wanted property and assign the pairs to the object.
const
array = [{ name: "read-web-courses" }, { name: "example" }, { name: "t_gql" }, { name: "ddddd" }],
result = Object.assign({}, array.map(({ name }) => name));
console.log(result);
You can use Array.reduce like below.
const a = [
{ name: "read-web-courses" },
{ name: "example" },
{ name: "t_gql" },
{ name: "ddddd" },
];
const convert = arr => (
arr.reduce((total, value, index) => {
total[index] = value.name;
return total;
}, {})
)
console.log(convert(a));
This is accomplished using Array#reduce, where you can use the index from the reduce callback as the key of the new object:
const a = [ { name: "read-web-courses" }, { name: "example" }, { name: "t_gql" }, { name: "ddddd" }];
const res = a.reduce((r, o, i) => {
r[i] = o.name;
return r;
}, {});
console.log(res);
Also one more approach using Object#fromEntries and Array#map, where each object is converted to an array of key, value pairs:
const a = [ { name: "read-web-courses" }, { name: "example" }, { name: "t_gql" }, { name: "ddddd" }];
const res = Object.fromEntries(a.map((o, i) => [i, o.name]));
console.log(res)
I would like to know how to change nested array object to object depending on key in javascript
I have objects obj1 and obj2, depending on key item type change the object.
function changeObj(obj){
let result = obj.reduce(function (acc, item) {
if(item.items.trim() !== "" && item.key.trim() !== ""){
acc[item.key] = item.items
return acc
}
return acc
}, {});
return result;
}
let result = this.changeObj(obj2)
var obj1 = [
{ id:0, items:["SG","AU"], count: 2, key:"countries"},
{ id:1, items:["finance"], count: 3 key:"info"}
]
var obj2 = [
{ id:0, items: "SG", key: "country"},
{ id:1, items: "details", key: "info"}
]
Expected Output:
// if items key is array
{
fields: {
countries: ["SG","AU",2],
info: ["finance",3]
}
}
//if items key is string
{
fields: {
country: "SG",
info: "details"
}
}
I think the reason your code is not running is because the wrong format of your objects (1 and 2). Your code is okay except the condition because trim() only works on string type so it errors on array. Try this code snippet
function changeObj(obj){
let result = obj.reduce(function (acc, item) {
acc[item.key] = item.items;
return acc;
}, {});
return result;
}
var obj1 = [
{ id:0, items:["SG","AU"], count: 2, key:"countries"},
{ id:1, items:["finance"], count: 3, key:"info"}
]
var obj2 = [
{ id:0, items: "SG", key: "country"},
{ id:1, items: "details", key: "info"}
]
console.log(changeObj(obj1));
const changeObj = obj =>
obj.reduce((acc, item) => {
if (Array.isArray(item.items)) {
acc[item.key] = [...item.items, item.count];
} else {
acc[item.key] = item.items;
}
return acc;
}, {});
var obj1 = [
{ id: 0, items: ['SG', 'AU'], count: 2, key: 'countries' },
{ id: 1, items: ['finance'], count: 3, key: 'info' }
];
var obj2 = [
{ id: 0, items: 'SG', key: 'country' },
{ id: 1, items: 'details', key: 'info' }
];
console.log(changeObj(obj1));
console.log(changeObj(obj2));
or cleaned up even more
const changeObj = obj =>
obj.reduce((acc, { items, key, count }) => {
Array.isArray(items) ? (acc[key] = [...items, count]) : (acc[key] = items);
return acc;
}, {});
var obj1 = [
{ id: 0, items: ['SG', 'AU'], count: 2, key: 'countries' },
{ id: 1, items: ['finance'], count: 3, key: 'info' }
];
var obj2 = [
{ id: 0, items: 'SG', key: 'country' },
{ id: 1, items: 'details', key: 'info' }
];
console.log(changeObj(obj1));
console.log(changeObj(obj2));
I have two arrays, and now I want to merge the two arrays.
The first array：
var data = [
{ name: 'aa', value: 1 },
{ name: 'bb', value: 2 },
{ name: 'cc', value: 3 }
];
Two arrays:
var data2 = [
{ name: 'aa' },
{ name: 'bb' },
{ name: 'cc' },
{ name: 'dd' },
{ name: 'ee' }
];
I want to merge them into this:
var data3 = [
{name: 'aa', value: 1},
{name: 'bb', value: 2},
{name: 'cc', value: 3},
{name: 'dd', value: 0},
{name: 'ee', value: 0}
];
console.log(data3)
At present, my experience is not enough. Please help me solve this problem.
Thanks in advance.
You can try following based on following assumptions
data2 is a collection of names and expecting its length to be always more than length of data
Order of objects can be different
var data = [
{ name: 'aa', value: 1 },
{ name: 'bb', value: 2 },
{ name: 'cc', value: 3 }
];
var data2 = [
{ name: 'aa' },
{ name: 'bb' },
{ name: 'cc' },
{ name: 'dd' },
{ name: 'ee' }
];
// Iterate over the names array
var data3 = data2.map(({name}) => {
// get the matched object in data corresponding to the name
var match = data.find((obj) => obj.name === name);
// if found, return value else default value to 0
return match ? match : {name, value : 0};
});
console.log(data3);
If the input arrays are indeed in order like that, then a simple .map would suffice:
var data = [
{ name: 'aa', value: 1 },
{ name: 'bb', value: 2 },
{ name: 'cc', value: 3 }
];
var data2 = [
{ name: 'aa' },
{ name: 'bb' },
{ name: 'cc' },
{ name: 'dd' },
{ name: 'ee' }
];
const output = data2.map(({ name }, i) => ({ name, value: data[i] ? data[i].value : 0 }));
console.log(output);
Create an object lookup for each name using array#reduce. Extract all the values using the Object.values() from the object lookup.
const data1 = [ { name: 'aa', value: 1 }, { name: 'bb', value: 2 }, { name: 'cc', value: 3 } ],
data2 = [ { name: 'aa' }, { name: 'bb' }, { name: 'cc' }, { name: 'dd' }, { name: 'ee' } ],
result = Object.values([data1, data2].reduce((r,a) => {
a.forEach(({name, value = 0}) => {
r[name] = name in r ? r[name] : {name, value};
});
return r;
},{}));
console.log(result);
You can array#concat both the arrays and using array#reduce create an object lookup and then get all the values using the Object.values().
const data1 = [ { name: 'aa', value: 1 }, { name: 'bb', value: 2 }, { name: 'cc', value: 3 } ],
data2 = [ { name: 'aa' }, { name: 'bb' }, { name: 'cc' }, { name: 'dd' }, { name: 'ee' } ],
result = Object.values(data1.concat(data2).reduce((r,{name, value=0}) => {
r[name] = name in r ? r[name] : {name, value};
return r;
},{}));
console.log(result);
var data = [
{ name: 'aa', value: 1 },
{ name: 'bb', value: 2 },
{ name: 'cc', value: 3 }
];
var data2 = [
{ name: 'aa' },
{ name: 'bb' },
{ name: 'cc' },
{ name: 'dd' },
{ name: 'ee' }
];
let output = new Array(data2.length).fill(data2.length).map(v => new Object());
// Logic
data.forEach((val2)=> {
data2.forEach((val, i)=> {
if (val.name == val2.name){
output[i]["name"] = val.name
output[i]["value"] = val2.value
} else{
output[i]["name"] = val.name
}
})
})
output.map((val,i) => {
if (!val.hasOwnProperty("value")){
console.log(val)
val["value"] = 0
}
})
console.log("------Your Expected Format", output)