/// <summary>
/// 改变元素的计算空间
/// </summary>
/// <param name="space">新的计算空间，为null即为默认计算空间</param>
/// <param name="newInstance">是否返回新的实例（如果为null，即为不确定）</param>
/// <param name="maxDecimalPlaces">最大保留小数位数</param>
/// <returns></returns>
public override IOperationSpaceElement ChangeOperationSpace(OperationSpace space = null, bool?newInstance = null, int?maxDecimalPlaces = null)
{
if (space == null)
{
space = OperationSpace.DefaultSpace;
}
var mdp = maxDecimalPlaces.HasValue ? Math.Min(maxDecimalPlaces.Value, space.DefaultMaxDecimalPlaces) : space.DefaultMaxDecimalPlaces;
if (newInstance == true)
{
var new_num = new RationalNum(this, null, true)
{
Space = space,
MaxDecimalPlaces = mdp,
numerator = (NaturalNumStr)numerator.ChangeOperationSpace(space, newInstance),
denominator = (NaturalNumStr)denominator.ChangeOperationSpace(space, newInstance)
};
return(new_num);
}
else
{
valueChanged = true;
Space = space;
MaxDecimalPlaces = mdp;
numerator = (NaturalNumStr)numerator.ChangeOperationSpace(space, newInstance);
denominator = (NaturalNumStr)denominator.ChangeOperationSpace(space, newInstance);
return(this);
}
}
/// <summary>
/// 用分式初始化
/// </summary>
/// <param name="numerator">分子</param>
/// <param name="denominator">分母</param>
/// <param name="positiveOrNegative">正负性</param>
/// <param name="space">计算空间</param>
/// <param name="maxDecimalPlaces">最大保留小数位数</param>
public RationalNum(NaturalNumStr numerator, NaturalNumStr denominator, int positiveOrNegative = 1, OperationSpace space = null, int?maxDecimalPlaces = null)
: base(null, space ?? numerator.Space, maxDecimalPlaces)
{
if (space == null && numerator.Space != denominator.Space)
{
throw new ProgramInterruptException(ProgramInterruptExceptionType.IllegalValue);
}
else
{
space = space ?? numerator.Space;
}
this.numerator = (NaturalNumStr)numerator.ChangeOperationSpace(space);
this.denominator = (NaturalNumStr)denominator.ChangeOperationSpace(space);
this.PositiveOrNegative = positiveOrNegative;
FractionReduction();
}