// Copyright Eric Chauvin 2015 - 2018.
internal int Reduce(Integer Result, Integer ToReduce)
{
try
{
if (ToReduce.ParamIsGreater(CurrentModReductionBase))
{
Result.Copy(ToReduce);
return(Result.GetIndex());
}
if (GeneralBaseArray == null)
{
throw(new Exception("SetupGeneralBaseArray() should have already been called."));
}
Result.SetToZero();
int TopOfToReduce = ToReduce.GetIndex() + 1;
if (TopOfToReduce > GeneralBaseArray.Length)
{
throw(new Exception("The Input number should have been reduced first. HowManyToAdd > GeneralBaseArray.Length"));
}
// If it gets this far then ToReduce is at
// least this big.
int HighestCopyIndex = CurrentModReductionBase.GetIndex();
Result.CopyUpTo(ToReduce, HighestCopyIndex - 1);
int BiggestIndex = 0;
for (int Count = HighestCopyIndex; Count < TopOfToReduce; Count++)
{
// The size of the numbers in GeneralBaseArray
// are all less than the size of GeneralBase.
// This multiplication by a uint is with a
// number that is not bigger than GeneralBase.
// Compare this with the two full Muliply()
// calls done on each digit of the quotient
// in LongDivide3().
// AccumulateBase is set to a new value here.
int CheckIndex = IntMath.MultiplyUIntFromCopy(AccumulateBase, GeneralBaseArray[Count], ToReduce.GetD(Count));
if (CheckIndex > BiggestIndex)
{
BiggestIndex = CheckIndex;
}
Result.Add(AccumulateBase);
}
return(Result.GetIndex());
}
catch (Exception Except)
{
throw(new Exception("Exception in ModularReduction(): " + Except.Message));
}
}
