public void ShiftRight(FastInteger fastint)
{
if (fastint.Sign <= 0)
{
return;
}
if (fastint.CanFitInInt32())
{
this.ShiftRightInt(fastint.ToInt32());
}
else
{
EInteger bi = fastint.ToEInteger();
while (bi.Sign > 0)
{
var count = 1000000;
if (bi.CompareTo((EInteger)1000000) < 0)
{
count = (int)bi;
}
this.ShiftRightInt(count);
bi -= (EInteger)count;
if (this.isSmall ? this.shiftedSmall == 0 :
this.shiftedBigInt.IsZero)
{
break;
}
}
}
}
public static FastIntegerFixed FromFastInteger(FastInteger fi)
{
if (fi.CanFitInInt32())
{
return(FromInt32(fi.ToInt32()));
}
else
{
return(FastIntegerFixed.FromBig(fi.ToEInteger()));
}
}
public void ShiftToDigits(
FastInteger bits,
FastInteger preShift,
bool truncate)
{
if (bits.Sign < 0)
{
throw new ArgumentException("bits's sign(" + bits.Sign +
") is less than 0");
}
if (preShift != null && preShift.Sign > 0)
{
this.knownBitLength = this.knownBitLength ?? this.CalcKnownBitLength();
// DebugUtility.Log("bits=" + bits + " pre=" + preShift + " known=" +
// (//kbl) + " [" + this.shiftedBigInt + "]");
if (this.knownBitLength.CompareTo(bits) <= 0)
{
// Known digit length is already small enough
// NOTE: For BitShiftAccumulator, truncating and shifting
// are the same, unlike in DigitShiftAccumulator
this.ShiftRight(preShift);
VerifyKnownLength();
return;
}
else
{
FastInteger bitDiff = this.knownBitLength.Copy()
.Subtract(bits);
// DebugUtility.Log("bitDiff=" + bitDiff);
int cmp = bitDiff.CompareTo(preShift);
if (cmp <= 0)
{
// NOTE: For BitShiftAccumulator, truncating and shifting
// are the same, unlike in DigitShiftAccumulator
this.ShiftRight(preShift);
VerifyKnownLength();
return;
}
else
{
// NOTE: For BitShiftAccumulator, truncating and shifting
// are the same, unlike in DigitShiftAccumulator
this.ShiftRight(bitDiff);
VerifyKnownLength();
return;
}
}
}
if (bits.CanFitInInt32())
{
this.ShiftToDigitsInt(bits.ToInt32());
VerifyKnownLength();
}
else
{
this.knownBitLength = this.knownBitLength ?? this.CalcKnownBitLength();
EInteger bigintDiff = this.knownBitLength.ToEInteger();
EInteger bitsBig = bits.ToEInteger();
bigintDiff -= (EInteger)bitsBig;
if (bigintDiff.Sign > 0)
{
// current length is greater than the
// desired bit length
this.ShiftRight(FastInteger.FromBig(bigintDiff));
}
VerifyKnownLength();
}
}
public static EInteger ReduceTrailingZeros(
EInteger bigmant,
FastInteger exponentMutable,
int radix,
FastInteger digits,
FastInteger precision,
FastInteger idealExp)
{
#if DEBUG
if (precision != null && digits == null)
{
throw new ArgumentException("doesn't satisfy precision==null ||" +
"\u0020digits!=null");
}
if (!(bigmant.Sign >= 0))
{
throw new ArgumentException("doesn't satisfy bigmant.Sign >= 0");
}
#endif
if (bigmant.IsZero)
{
exponentMutable.SetInt(0);
return(bigmant);
}
if (radix == 2)
{
if (!bigmant.IsEven)
{
return(bigmant);
}
long lowbit = bigmant.GetLowBitAsInt64();
if (lowbit != Int64.MaxValue)
{
if (precision != null && digits.CompareTo(precision) >= 0)
{
// Limit by digits minus precision
EInteger tmp = digits.ToEInteger().Subtract(precision.ToEInteger());
if (tmp.CompareTo(EInteger.FromInt64(lowbit)) < 0)
{
lowbit = tmp.ToInt64Checked();
}
}
if (idealExp != null && exponentMutable.CompareTo(idealExp) <= 0)
{
// Limit by idealExp minus exponentMutable
EInteger tmp =
idealExp.ToEInteger().Subtract(exponentMutable.ToEInteger());
if (tmp.CompareTo(EInteger.FromInt64(lowbit)) < 0)
{
lowbit = tmp.ToInt64Checked();
}
}
bigmant = (lowbit <= Int32.MaxValue) ?
bigmant.ShiftRight((int)lowbit) :
bigmant.ShiftRight(EInteger.FromInt64(lowbit));
if (digits != null)
{
digits.SubtractInt64(lowbit);
}
if (exponentMutable != null)
{
exponentMutable.AddInt64(lowbit);
}
return(bigmant);
}
}
var bigradix = (EInteger)radix;
var bitsToShift = new FastInteger(0);
while (!bigmant.IsZero)
{
if (precision != null && digits.CompareTo(precision) == 0)
{
break;
}
if (idealExp != null && exponentMutable.CompareTo(idealExp) == 0)
{
break;
}
EInteger bigrem;
EInteger bigquo;
EInteger[] divrem = bigmant.DivRem(bigradix);
bigquo = divrem[0];
bigrem = divrem[1];
if (!bigrem.IsZero)
{
break;
}
bigmant = bigquo;
exponentMutable.Increment();
if (digits != null)
{
digits.Decrement();
}
}
return(bigmant);
}
private T PostProcessEx(
T thisValue,
EContext ctxDest,
EContext ctxSrc,
bool afterDivision,
bool afterQuantize)
{
int thisFlags = this.GetHelper().GetFlags(thisValue);
if (ctxDest != null && ctxSrc != null)
{
if (ctxDest.HasFlags)
{
if (!ctxSrc.ClampNormalExponents)
{
ctxSrc.Flags &= ~EContext.FlagClamped;
}
ctxDest.Flags |= ctxSrc.Flags;
if ((ctxSrc.Flags & EContext.FlagSubnormal) != 0)
{
// Treat subnormal numbers as underflows
ctxDest.Flags |= EContext.FlagUnderflow |
EContext.FlagSubnormal | EContext.FlagInexact | EContext.FlagRounded;
}
}
}
if ((thisFlags & BigNumberFlags.FlagSpecial) != 0)
{
return((ctxDest.Flags == 0) ? this.SignalInvalid(ctxDest) : thisValue);
}
EInteger mant = this.GetHelper().GetMantissa(thisValue).Abs();
if (mant.IsZero)
{
return(afterQuantize ? this.GetHelper().CreateNewWithFlags(
mant,
this.GetHelper().GetExponent(thisValue),
0) : this.wrapper.RoundToPrecision(
this.GetHelper().ValueOf(0),
ctxDest));
}
if (afterQuantize)
{
return(thisValue);
}
EInteger exp = this.GetHelper().GetExponent(thisValue);
if (exp.Sign > 0)
{
FastInteger fastExp = FastInteger.FromBig(exp);
if (ctxDest == null || !ctxDest.HasMaxPrecision)
{
mant = this.GetHelper().MultiplyByRadixPower(mant, fastExp);
return(this.GetHelper().CreateNewWithFlags(
mant,
EInteger.Zero,
thisFlags));
}
if (!ctxDest.ExponentWithinRange(exp))
{
return(thisValue);
}
FastInteger prec = FastInteger.FromBig(ctxDest.Precision);
FastInteger digits = this.GetHelper().GetDigitLength(mant);
prec.Subtract(digits);
if (prec.Sign > 0 && prec.CompareTo(fastExp) >= 0)
{
mant = this.GetHelper().MultiplyByRadixPower(mant, fastExp);
return(this.GetHelper().CreateNewWithFlags(
mant,
EInteger.Zero,
thisFlags));
}
if (afterDivision)
{
int radix = this.GetHelper().GetRadix();
mant = NumberUtility.ReduceTrailingZeros(
mant,
fastExp,
radix,
null,
null,
null);
thisValue = this.GetHelper().CreateNewWithFlags(
mant,
fastExp.ToEInteger(),
thisFlags);
}
}
else if (afterDivision && exp.Sign < 0)
{
FastInteger fastExp = FastInteger.FromBig(exp);
int radix = this.GetHelper().GetRadix();
mant = NumberUtility.ReduceTrailingZeros(
mant, fastExp, radix, null, null, new FastInteger(0));
thisValue = this.GetHelper().CreateNewWithFlags(
mant,
fastExp.ToEInteger(),
thisFlags);
}
return(thisValue);
}