I have an array with values per date but would like to sum up all values on hour instead of separate date/hour. I guess I could iterate over it and remove yyyy-mm-dd and then sum up on duplicate hour object but is there a smarter way?
{
"series": [
{
"value": 1,
"category": "2021-03-04T04:00:00.000"
},
{
"value": 2,
"category": "2021-03-04T05:00:00.000"
},
{
"value": 3,
"category": "2021-03-04T06:00:00.000"
},
{
"value": 1,
"category": "2021-03-05T04:00:00.000"
},
{
"value": 2,
"category": "2021-03-05T05:00:00.000"
},
{
"value": 3,
"category": "2021-03-05T06:00:00.000"
}
]
}
]
So the array below should only be:
[
{
"series": [
{
"value": 2,
"category": "04:00:00.000"
},
{
"value": 4,
"category": "05:00:00.000"
},
{
"value": 6,
"category": "06:00:00.000"
}
]
}
]
Map and reduce - you can split in the reduce but this is more readable
const data = {
"series": [
{ "value": 1, "category": "2021-03-04T04:00:00.000" },
{ "value": 2, "category": "2021-03-04T05:00:00.000" },
{ "value": 3, "category": "2021-03-04T06:00:00.000" },
{ "value": 1, "category": "2021-03-05T04:00:00.000" },
{ "value": 2, "category": "2021-03-05T05:00:00.000" },
{ "value": 3, "category": "2021-03-05T06:00:00.000" }
]
}
const newData = data.series
.map(item => ({value:item.value, category: item.category.split("T")[1]})) // cut the date off
.reduce((acc,cur) => {
const item = acc.find(({category}) => category === cur.category); // find if we already have the time in the array we are creating
if (item) item.value += cur.value; // if yes, add the value
else acc.push(cur); // else push the current object
return acc;
},
[])
console.log(newData)Use Array.reduce
Logic
Array.reduce.category by splitting the sting on T.const data = {
series: [
{ value: 1, category: "2021-03-04T04:00:00.000" },
{ value: 2, category: "2021-03-04T05:00:00.000" },
{ value: 3, category: "2021-03-04T06:00:00.000" },
{ value: 1, category: "2021-03-05T04:00:00.000" },
{ value: 2, category: "2021-03-05T05:00:00.000" },
{ value: 3, category: "2021-03-05T06:00:00.000" },
],
};
const result = data.series.reduce((acc, curr) => {
const time = curr.category.split("T")[1];
const accNode = acc.find((node) => node.category === time);
if (accNode) {
accNode.value += curr.value;
} else {
acc.push({ value: curr.value, category: time });
}
return acc;
}, []);
console.log({
series: result,
});