The original array has several objects within it, each of these objects has three properties (timestamp, name and age).
If multiple timestamps in a row are 15 minutes apart, they will be grouped into the same object. Afterwards, a new property called end will be added, which will be the timestamp value of the last element of this group plus 15 minutes.
If there are not several elements in a row with a difference of 15 minutes between them, the end property will have the timestamp plus 15 minutes as a value.
This is my current code:
const data = [
{
timestamp: '2021-11-23T14:15:00+0000',
name: 'John',
age: 25,
},
{
timestamp: '2021-11-23T14:30:00+0000',
name: 'John',
age: 25,
},
{
timestamp: '2021-11-23T14:45:00+0000',
name: 'John',
age: 25,
},
{
timestamp: '2021-11-23T15:45:00+0000',
name: 'John',
age: 25,
},
{
timestamp: '2021-11-23T14:15:00+0000',
name: 'Anne',
age: 32,
},
{
timestamp: '2021-11-23T14:30:00+0000',
name: 'Anne',
age: 32,
},
{
timestamp: '2021-11-23T14:45:00+0000',
name: 'Anne',
age: 32,
},
{
timestamp: '2021-11-23T15:45:00+0000',
name: 'Anne',
age: 32,
},
]
const newArray = data.reduce((accumulator, current) => {
const end = new Date(Date.parse(current.timestamp) + 15 * 60 * 1000)
if (accumulator.length === 0) {
accumulator.push({
...current,
end,
})
} else {
const last = accumulator[accumulator.length - 1]
if (last.name === current.name && last.age === current.age) {
last.end = end
} else {
accumulator.push({
...current,
end,
})
}
}
return accumulator
}, [])
console.log(newArray)However the end result of my code is not exactly what I want. I would like my result to be like this:
[
{
timestamp: '2021-11-23T14:15:00+0000',
name: 'John',
age: 25,
end: '2021-11-23T15:00:00+0000'
},
{
timestamp: '2021-11-23T15:45:00+0000',
name: 'John',
age: 25,
end: '2021-11-23T16:00:00+0000'
},
{
timestamp: '2021-11-23T14:15:00+0000',
name: 'Anne',
age: 32,
end: '2021-11-23T15:00:00+0000'
},
{
timestamp: '2021-11-23T15:45:00+0000',
name: 'Anne',
age: 32,
end: '2021-11-23T16:00:00+0000'
}
]
You could search for the last interval and update end if found. Otherwise add a new object.
const data = [{ timestamp: '2021-11-23T14:15:00+0000', name: 'John', age: 25 }, { timestamp: '2021-11-23T14:30:00+0000', name: 'John', age: 25 }, { timestamp: '2021-11-23T14:45:00+0000', name: 'John', age: 25 }, { timestamp: '2021-11-23T15:45:00+0000', name: 'John', age: 25 }, { timestamp: '2021-11-23T14:15:00+0000', name: 'Anne', age: 32 }, { timestamp: '2021-11-23T14:30:00+0000', name: 'Anne', age: 32 }, { timestamp: '2021-11-23T14:45:00+0000', name: 'Anne', age: 32 }, { timestamp: '2021-11-23T15:45:00+0000', name: 'Anne', age: 32 }]
const newArray = data.reduce((accumulator, current) => {
const
end = new Date(Date.parse(current.timestamp) + 15 * 60 * 1000).toISOString(),
item = accumulator.find(o =>
o.name === current.name &&
o.end === new Date(current.timestamp).toISOString()
);
if (item) item.end = end;
else accumulator.push({ ...current, end });
return accumulator;
}, [])
console.log(newArray);.as-console-wrapper { max-height: 100% !important; top: 0; }You can use Array.reduce() to get the required result as in your own code, but we can make a slight change to update the lastItem in the accumulator array if
If this condition isn't met we simply add to the accumulator array.
const data = [ { timestamp: '2021-11-23T14:15:00+0000', name: 'John', age: 25, }, { timestamp: '2021-11-23T14:30:00+0000', name: 'John', age: 25, }, { timestamp: '2021-11-23T14:45:00+0000', name: 'John', age: 25, }, { timestamp: '2021-11-23T15:45:00+0000', name: 'John', age: 25, }, { timestamp: '2021-11-23T14:15:00+0000', name: 'Anne', age: 32, }, { timestamp: '2021-11-23T14:30:00+0000', name: 'Anne', age: 32, }, { timestamp: '2021-11-23T14:45:00+0000', name: 'Anne', age: 32, }, { timestamp: '2021-11-23T15:45:00+0000', name: 'Anne', age: 32, }, ]
const result = data.reduce((acc, { timestamp, name, age }) => {
let lastItem = acc[acc.length - 1];
let end = new Date(Date.parse(timestamp) + 15*60*1000);
// If the current row matches just update the end time
if (lastItem && lastItem.name === name && (Date.parse(lastItem.end) - Date.parse(timestamp) >= 0)) {
lastItem.end = end;
} else {
acc.push({ timestamp, name, age, end });
}
return acc;
}, [])
console.log(result).as-console-wrapper { max-height: 100% !important; top: 0; }