$round

Rounds a number to the nearest integer or to a specified decimal place.

Syntax

{ "$round": [ <numberExpression>, <placeExpression?> ] }

• Omit the second argument to round to the nearest integer.
• Supply a positive place to round to decimal places, or a negative value to round to tens, hundreds, etc.

Example

Input

{ "score": 87.456 }

Stage

{ "$project": { "scoreRounded": { "$round": ["$score", 1] } } }

Output

{ "scoreRounded": 87.5 }