How to return float value with zero fraction in MongoDB? -

i trying retrieve float values mongodb 0 fraction. doesn't work expect to.

i.e. inserted doc:
db.collection.insert({ _id: 1, floatval: 10.0 })

while retrieving gives as:

{         "_id": 1,         "floatval": 10     }

whereas want result as:

{         "_id": 1,         "floatval" : 10.0     }

Prevent