Round a number value to a number of significant digits. The significance defaults to two digits.

Example:

{{ 1256|round_significant }}
{{ 1256|round_significant:1 }}
{{ 1256|round_significant:3 }}

Results in:

1300
1000
1260

Floating point values are also rounded to a number of digits. For example if n is set to 1256.78 then:

{{ n|round_significant }}
{{ n|round_significant:3 }}
{{ n|round_significant:5 }}

Results in:

1300.0
1260.0
1256.8

Input values that are not a number are converted to a floating point value. If the conversion fails then undefined is returned.