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- $trunc (aggregation)
$trunc (aggregation)¶
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Definition¶
-
$trunc
¶ New in version 3.2.
Truncates a number to its integer.
$trunc
has the following syntax:The
<number>
expression can be any valid expression as long as it resolves to a number. For more information on expressions, see Expressions.
Behavior¶
If the argument resolves to a value of null
or refers to a field that is
missing, $trunc
returns null
. If the argument resolves to
NaN
, $trunc
returns NaN
.
Example | Results |
---|---|
{ $trunc: 0 } |
0 |
{ $trunc: 7.80 } |
7 |
{ $trunc: -2.3 } |
-2 |
Example¶
A collection named samples
contains the following documents:
The following example returns both the original value and the truncated value:
The operation returns the following results: