How can I group by Date
and transform the following data
// PROVIDED INPUT
[
{
"Date": "2021/Dec/01",
"Media category": "Canvas",
"Printed square meters": 244.58
},
{
"Date": "2021/Dec/01",
"Media category": "Film",
"Printed square meters": 152.62
},
{
"Date": "2021/Dec/01",
"Media category": "Heavy paper > 200gsm",
"Printed square meters": 256.02000000000004
},
{
"Date": "2021/Dec/02",
"Media category": "Textile",
"Printed square meters": 144.95999999999998
},
{
"Date": "2021/Dec/02",
"Media category": "Thick film > 200 um",
"Printed square meters": 153.37
},
{
"Date": "2021/Dec/02",
"Media category": "Paper",
"Printed square meters": 217.2
}, ...
]
into this with JavaScript. I tried to accomplish this with Lodash's groupBy()
and mergeWith()
, but I am not getting anywhere:
// DESIRED OUTPUT
[
{
"Date": "2021/Dec/01",
"Canvas": 244.58,
"Film": 152.62
"Heavy paper > 200gsm": 256.02000000000004
},
{
"Date": "2021/Dec/02",
"Textile": 144.95999999999998,
"Thick film > 200 um": 153.37
"Paper": 217.2
}, ...
]
Also, is it possible to group by two keys - i.e Date
and Printer id
:
// PROVIDED INPUT
[
{
"Date": "2021/Dec/01",
"Printer id": "700",
"Media category": "Canvas",
"Printed square meters": 244.58
},
{
"Date": "2021/Dec/01",
"Printer id": "700",
"Media category": "Film",
"Printed square meters": 152.62
},
{
"Date": "2021/Dec/01",
"Printer id": "701",
"Media category": "Heavy paper > 200gsm",
"Printed square meters": 256.02000000000004
},
{
"Date": "2021/Dec/01",
"Printer id": "701",
"Media category": "Textile",
"Printed square meters": 144.95999999999998
}, ...
]
// DESIRED OUTPUT
[
{
"Date": "2021/Dec/01",
"Printer id": "700",
"Canvas": 244.58,
"Film": 152.62
},
{
"Date": "2021/Dec/01",
"Printer id": "701",
"Heavy paper > 200gsm": 256.02000000000004,
"Textile": 144.95999999999998
}, ...
I tried doing the first one with this code, but got no idea how to transform the fields:
// What I tried doing
console.log(_(data)
.groupBy('Date')
.map(g => _.mergeWith({}, ...g, (obj, src) =>
_.isArray(obj) ? obj.concat(src) : undefined))
.value());
Checked many questions before submitting this one but none has the the transformation of fields.
CodePudding user response:
You can create a computed key on Date
and Printer id
and group based on this key.
const data = [ { "Date": "2021/Dec/01", "Printer id": "700", "Media category": "Canvas", "Printed square meters": 244.58 }, { "Date": "2021/Dec/01", "Printer id": "700", "Media category": "Film", "Printed square meters": 152.62 }, { "Date": "2021/Dec/01", "Printer id": "701", "Media category": "Heavy paper > 200gsm", "Printed square meters": 256.02000000000004 }, { "Date": "2021/Dec/01", "Printer id": "701", "Media category": "Textile", "Printed square meters": 144.95999999999998 }],
result = Object.values(data.reduce((r, o) => {
let key = o.Date '-' o['Printer id'];
r[key] ??= {Date: o.Date, 'Printer id': o['Printer id']};
r[key][o['Media category']] = (r[key][o['Media category']] ?? 0) o['Printed square meters'];
return r;
},{}));
console.log(result);