round function

dynamic round(dynamic x, [ int decimalPlaces = 0 ])

Rounds the number x to the specified number of decimalPlaces.

If decimalPlaces is not provided or is 0, the function rounds x to the nearest whole number. Otherwise, it rounds x to the desired number of decimal places.

Example:

print(round(123.4567, 2)); // Output: 123.46
print(round(123.4567));    // Output: 123
print(round(Complex(3.7, 2.9))); // Output: Complex(4, 3)

x is the number to be rounded. decimalPlaces specifies the number of decimal places to round to.

Implementation

dynamic round(dynamic x, [int decimalPlaces = 0]) {
  if (x is num) {
    if (decimalPlaces == 0) {
      return x.round();
    } else {
      return (x * math.pow(10, decimalPlaces)).round() / math.pow(10, decimalPlaces);
    }
  } else if (x is Complex) {
    return x.roundTo(decimals: decimalPlaces).simplify();
  } else {
    throw ArgumentError('Input should be either num or Complex');
  }
}