how to ristrict double to three decimal in flutter code example

Example 1: double variable into 2 decimal places flutter

double num1 = double.parse((12.3412).toStringAsFixed(2));
// 12.34

double num2 = double.parse((12.5668).toStringAsFixed(2));
// 12.57

double num3 = double.parse((-12.3412).toStringAsFixed(2));
// -12.34

double num4 = double.parse((-12.3456).toStringAsFixed(2));
// -12.35

Example 2: double 2 decimal places flutter

/// Define an extension:
extension Ex on double {
  double toPrecision(int n) => double.parse(toStringAsFixed(n));
}

/// Usage:
void main() {
  double d = 2.3456789;
  double d1 = d.toPrecision(1); // 2.3
  double d2 = d.toPrecision(2); // 2.35
  double d3 = d.toPrecision(3); // 2.345
}