# roundToDouble method Null safety

Returns the double integer value closest to `this`

.

Rounds away from zero when there is no closest integer:
`(3.5).roundToDouble() == 4`

and `(-3.5).roundToDouble() == -4`

.

If this is already an integer valued double, including `-0.0`

, or it is a
non-finite double value, the value is returned unmodified.

For the purpose of rounding, `-0.0`

is considered to be below `0.0`

,
and `-0.0`

is therefore considered closer to negative numbers than `0.0`

.
This means that for a value, `d`

in the range `-0.5 < d < 0.0`

,
the result is `-0.0`

.

The result is always a double. If this is a numerically large integer, the result may be an infinite double.

## Implementation

`double? roundToDouble() => value?.roundToDouble();`