I have an object array like this:
var input = [{ time: '11:01:00', data: 'a,b,c' }, { time: '11:01:11', data: 'a,b,c' }]
After I call:
var output1 = input.map(a => a.data);
console.log(output1);
The result would be:
[
"a,b,c",
"a,b,c"
]
Now I want the final output will be:
[
{data: ["a","a"]},
{data: ["b","b"]},
{data: ["c","c"]},
]
I have tried many way but no hope to do this.
Your operation is essentially a matrix transposition, let's code it as such:
let transpose = matrix => matrix[0].map((_, col) =>
matrix.map(row => row[col]))
//
var input = [{ time: '...', data: 'a,b,c' }, { time: '...', data: 'x,y,z' }]
let result = transpose(
input.map(o => o.data.split(','))
).map(data => ({data}))
console.log(result)Use Array.flatMap() with Array.slice() to get an array of strings. Then reduce it to an object, with equal strings grouped together, and convert back to an array using Object.values():
const input = [{ time: '11:01:00', data: 'a,b,c' }, { time: '11:01:11', data: 'a,b,c' }]
const result = Object.values(
input.flatMap(o => o.data.split(','))
.reduce((acc, c) => {
if(!acc[c]) acc[c] = { data: [] }
acc[c].data.push(c)
return acc
}, {})
)
console.log(result)You could do it like this:
var input = [{ time: '11:01:00', data: 'a,b,c' }, { time: '11:01:11', data: 'a,b,c' }];
var output1 = input.map(a => a.data);
// Let's split the strings in order to have an array ('a', 'b', 'c')
output1 = output1.map( (data) => data.split(',') );
let valueMap = {};
// Loop through all the values
for (let list of output1) {
for (let element of list) {
// Use a dictionary to group all the identical values
if (!valueMap[element]) {
valueMap[element] = [element];
}
else {
valueMap[element].push(element);
}
}
}
// Get the values from the object and map it with the desired structure
let result = Object.values(valueMap).map( (lista) => ({ data: lista }) );
console.log(result);A single liner.
var input = [{ time: '11:01:00', data: 'a,b,c' }, { time: '11:01:11', data: 'a,b,c' }]
var output1 = input.map(a => a.data.split(','))[0].map((_, idx) => {return {data: input.map(a => a.data.split(',')[idx])}});
console.log(output1);