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t = db.mr2;
t.drop();
t.save( { comments : [ { who : "a" , txt : "asdasdasd" } ,
{ who : "b" , txt : "asdasdasdasdasdasdas" } ] } );
t.save( { comments : [ { who : "b" , txt : "asdasdasdaaa" } ,
{ who : "c" , txt : "asdasdasdaasdasdas" } ] } );
function m(){
for ( var i=0; i<this.comments.length; i++ ){
var c = this.comments[i];
emit( c.who , { totalSize : c.txt.length , num : 1 } );
}
}
function r( who , values ){
var n = { totalSize : 0 , num : 0 };
for ( var i=0; i<values.length; i++ ){
n.totalSize += values[i].totalSize;
n.num += values[i].num;
}
return n;
}
function reformat( r ){
var x = {};
r.find().forEach(
function(z){
x[z._id] = z.value;
}
);
return x;
}
function f( who , res ){
res.avg = res.totalSize / res.num;
return res;
}
res = t.mapReduce( m , r , { finalize : f } );
x = reformat( res );
assert.eq( 9 , x.a.avg , "A" );
assert.eq( 16 , x.b.avg , "B" );
assert.eq( 18 , x.c.avg , "C" );
res.drop();
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