JS: Dict of arrays combining by AND operation

Question

i use Angularjs. I have next data e.g:

let filters = {
                'async':[3,7],
                'gpu_freq':[400,500]
            };

Is there a better way to get the following combination then many loops?

[{
    'async': 3,
    'gpu_freq': 400
},{
    'async': 3,
    'gpu_freq': 50
},{
    'async': 7,
    'gpu_freq': 400
},{
    'async': 7,
    'gpu_freq': 500
}]

Number of filters can be different

Start with this https://stackoverflow.com/questions/12303989/cartesian-product-of-multiple-arrays-in-javascript — Wiktor Zychla, Oct 18 '18 at 11:15

Nina Scholz · Accepted Answer · 2018-10-18T11:26:51.783

You could get a cartesian product by iterating the values, if an array with objects call getCartesian again and build new objects.

This works for nested objects as well.

function getCartesian(object) {
    return Object.entries(object).reduce((r, [k, v]) => {
        var temp = [];
        r.forEach(s =>
            (Array.isArray(v) ? v : [v]).forEach(w =>
                (w && typeof w === 'object' ? getCartesian(w) : [w]).forEach(x =>
                    temp.push(Object.assign({}, s, { [k]: x }))
                )
            )
        );
        return temp;
    }, [{}]);
}

var filters = { async: [3, 7], gpu_freq: [400, 500] },
    cartesian = getCartesian(filters);

console.log(cartesian);

.as-console-wrapper { max-height: 100% !important; top: 0; }

but I need to calculate the data – Lola Oct 18 '18 at 11:24 — Lola, Oct 18 '18 at 11:24
@NinaScholz Removed :) Good job – Adrian Oct 18 '18 at 11:29 — Adrian, Oct 18 '18 at 11:29

JS: Dict of arrays combining by AND operation

1 Answers1