$atan2 (aggregation)
$atan2
New in version 4.2.
Returns the inverse tangent (arc tangent) of
y / x
, wherey
andx
are the first and second values passed to the expression respectively.$atan2
has the following syntax:{ $atan2: [ <expression 1>, <expression 2> ] } $atan2
takes any valid expression that resolves to a number.$atan2
returns values in radians. Use$radiansToDegrees
operator to convert the output value from radians to degrees.By default
$atan2
returns values as adouble
.$atan2
can 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 Expression Operators.
Behavior
null
and NaN

If either argument given to $atan2
is null
, the expression returns
null
. If either argument is NaN
, the expression returns NaN
.
If one argument is null
and the other is NaN
, the expression returns
null
.
Example | Results |
---|---|
{ $atan2: [ NaN, <value> ] } | NaN |
{ $atan2: [ <value>, NaN ] } | NaN |
{ $atan2: [ null, <value> ] } | null |
{ $atan2: [ <value>, null ] } | null |
{ $atan2: [ NaN, null ] } | null |
{ $atan2: [ null, NaN ] } | null |