public float GetSingleValue(RoundingMode m)
{
if (this.IsZero)
{
return(0.0f);
}
Tuple <BigRational, int> normalized = Normalize(this);
BigRational frac = normalized.Item1;
int expt = normalized.Item2;
expt += 127;
int loops = 24;
while (expt < 0 && loops > 0)
{
frac /= BigRational.Two;
expt += 1;
loops -= 1;
}
if (expt <= 0)
{
expt = 0; frac /= BigRational.Two;
}
if (expt > 254)
{
return((frac < BigRational.Zero) ? float.NegativeInfinity : float.PositiveInfinity);
}
int bits = GetInt32Value_Saturate((frac * singleFractionScale).RoundingOp(m));
if (bits < 0)
{
bits = (-bits) | unchecked ((int)0x80000000L);
}
bits &= unchecked ((int)0x807FFFFFL);
bits |= expt << 23;
return(BitConverter.ToSingle(BitConverter.GetBytes(bits), 0));
}
public double GetDoubleValue(RoundingMode m)
{
if (this.IsZero)
{
return(0.0);
}
Tuple <BigRational, int> normalized = Normalize(this);
BigRational frac = normalized.Item1;
int expt = normalized.Item2;
expt += 1023;
int loops = 53;
while (expt < 0 && loops > 0)
{
frac /= BigRational.Two;
expt += 1;
loops -= 1;
}
if (expt <= 0)
{
expt = 0; frac /= BigRational.Two;
}
if (expt > 2046)
{
return((frac < BigRational.Zero) ? double.NegativeInfinity : double.PositiveInfinity);
}
long bits = GetInt64Value_Saturate((frac * doubleFractionScale).RoundingOp(m));
if (bits < 0)
{
bits = (-bits) | unchecked ((long)0x8000000000000000L);
}
bits &= unchecked ((long)0x800FFFFFFFFFFFFFL);
bits |= (long)expt << 52;
return(BitConverter.Int64BitsToDouble(bits));
}
public BigInteger Round()
{
System.Diagnostics.Debug.Assert(denominator > BigInteger.Zero);
BigRational r = this + new BigRational(BigInteger.One, (BigInteger)2);
if (r.Denominator == BigInteger.One)
{
if (!r.Numerator.IsEven)
{
return(r.Numerator - BigInteger.One);
}
else
{
return(r.Numerator);
}
}
else
{
return(r.Floor());
}
}
public RationalDatum(BigRational value)
{
this.value = value;
}
public static Tuple <BigRational, int> Normalize(BigRational r)
{
if (r.IsNegative)
{
Tuple <BigRational, int> result = Normalize(-r);
return(new Tuple <BigRational, int>(-result.Item1, result.Item2));
}
Stack <BigRational> powers = new Stack <BigRational>();
Stack <int> exponents = new Stack <int>();
BigRational currentPower = null;
int currentExponent = 0;
int finalExponent = 0;
if (r < BigRational.One)
{
currentPower = BigRational.OneHalf;
currentExponent = -1;
while (r < currentPower)
{
powers.Push(currentPower);
exponents.Push(currentExponent);
currentPower *= currentPower;
currentExponent *= 2;
}
while (powers.Count > 0)
{
currentPower = powers.Pop();
currentExponent = exponents.Pop();
if (r < currentPower)
{
r /= currentPower;
finalExponent += currentExponent;
}
}
}
else
{
currentPower = BigRational.Two;
currentExponent = 1;
while (r > currentPower)
{
powers.Push(currentPower);
exponents.Push(currentExponent);
currentPower *= currentPower;
currentExponent *= 2;
}
while (powers.Count > 0)
{
currentPower = powers.Pop();
currentExponent = exponents.Pop();
if (r > currentPower)
{
r /= currentPower;
finalExponent += currentExponent;
}
}
}
while (r >= BigRational.Two)
{
r /= BigRational.Two;
finalExponent += 1;
}
while (r < BigRational.One)
{
r *= BigRational.Two;
finalExponent -= 1;
}
return(new Tuple <BigRational, int>(r, finalExponent));
}
public static BigRational Max(BigRational a, BigRational b)
{
return((a > b) ? a : b);
}
public static BigRational Min(BigRational a, BigRational b)
{
return((a < b) ? a : b);
}
