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$atan (aggregation)
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$atanNew in version 4.2.
Returns the inverse tangent (arc tangent) of a value.
$atanhas the following syntax:{ $atan: <expression> } $atantakes any valid expression that resolves to a number.$atanreturns values in radians. Use$radiansToDegreesoperator to convert the output value from radians to degrees.By default
$atanreturns values as adouble.$atancan also return values as a 128-bit decimal as long as the<expression>resolves to a 128-bit decimal value.For more information on expressions, see Expressions.
Behavior
null and NaN
If the argument resolves to a value of null or refers to a field
that is missing, $atan returns null. If the
argument resolves to NaN, $tan returns NaN.
Example | Results |
|---|---|
{ $atan: NaN } | NaN |
{ $atan: null } | null |