A few JavaScript functions to work with arrays, such as sum(), filter() and groupby().
Here are som examples.
var array = require('./array');
var a = [{name: "Peter"}, {name: "Edvin"}, {name: "Peter"}];
var grouped = array.groupby(a, function (d) {return d.name; });
Now grouped
is:
{ Peter: [ { name: 'Peter' }, { name: 'Peter' } ],
Edvin: [ { name: 'Edvin' } ] }
var array = require('./array');
var a = [{name: "Peter"}, {name: "Edvin"}, {name: "Peter"}];
var filtered = array.filter(a, function (d) {return d.name === "Edvin"; });
Now filtered
is ```[ { name: 'Edvin' } ]``.
var a = [{name: "Adam"}, {name: "Calle"}, {name: "Boo"}];
var sorted = array.sort(a, function (d) {return d.name; });
Now sorted
is:
[ { name: 'Calle' }, { name: 'Boo' }, { name: 'Adam' } ]
var a = [{name: "Adam", value: 5}, {name: "Calle", value: 5}, {name: "Boo", value: 5}, {name: "Boo", value: 5}, {name: "Calle", value: 7}];
var agg = array.aggregate(a, 'name', array.sum);
Now agg
is:
[ { name: 'Adam', value: 5 },
{ name: 'Calle', value: 12 },
{ name: 'Boo', value: 10 } ]