public double getDouble(String key, String description, double defaultValue) {
    String value = getArg(key, Double.toString(defaultValue));
    double parsed = Double.parseDouble(value);
    logArgValue(key, description, parsed);
    return parsed;
  }
Returns an argument as double.

@throws NumberFormatException if the argument cannot be parsed as a double
planetiler-core/src/main/java/com/onthegomap/planetiler/config/Arguments.java