console
var list = [{
"players": 1,
"num": 10000
},
{
"players": 2,
"num": 10000
}, {
"players": 3,
"num": 10000
}, {
"players": 4,
"num": 10000
}, {
"players": 5,
"num": 10000
}];
function groupByItem(item) {
if (item.players<3){
return item.players;
}else {
return '3 plus';
}
}
function mapValues(value){
return {"num":_.sumBy(value, "num")};
}
var output = _(list)
.groupBy(groupByItem )
.mapValues(mapValues)
.value();
$("#output").html(JSON.stringify(output));
<div id="output">
</div>
<div id="output1">
</div>