internal void DoSquare(Integer ToSquare)
{
if (ToSquare.GetIndex() == 0)
{
ToSquare.Square0();
return;
}
if (ToSquare.GetIndex() == 1)
{
ToSquare.Square1();
return;
}
if (ToSquare.GetIndex() == 2)
{
ToSquare.Square2();
return;
}
// Now Index is at least 3:
int DoubleIndex = ToSquare.GetIndex() << 1;
if (DoubleIndex >= Integer.DigitArraySize)
{
throw(new Exception("Square() overflowed."));
}
for (int Row = 0; Row <= ToSquare.GetIndex(); Row++)
{
if (ToSquare.GetD(Row) == 0)
{
for (int Column = 0; Column <= ToSquare.GetIndex(); Column++)
{
M[Column + Row, Row] = 0;
}
}
else
{
for (int Column = 0; Column <= ToSquare.GetIndex(); Column++)
{
M[Column + Row, Row] = ToSquare.GetD(Row) * ToSquare.GetD(Column);
}
}
}
// Add the columns up with a carry.
ToSquare.SetD(0, M[0, 0] & 0xFFFFFFFF);
ulong Carry = M[0, 0] >> 32;
for (int Column = 1; Column <= DoubleIndex; Column++)
{
ulong TotalLeft = 0;
ulong TotalRight = 0;
for (int Row = 0; Row <= Column; Row++)
{
if (Row > ToSquare.GetIndex())
{
break;
}
if (Column > (ToSquare.GetIndex() + Row))
{
continue;
}
TotalRight += M[Column, Row] & 0xFFFFFFFF;
TotalLeft += M[Column, Row] >> 32;
}
TotalRight += Carry;
ToSquare.SetD(Column, TotalRight & 0xFFFFFFFF);
Carry = TotalRight >> 32;
Carry += TotalLeft;
}
ToSquare.SetIndex(DoubleIndex);
if (Carry != 0)
{
ToSquare.SetIndex(ToSquare.GetIndex() + 1);
if (ToSquare.GetIndex() >= Integer.DigitArraySize)
{
throw(new Exception("Square() overflow."));
}
ToSquare.SetD(ToSquare.GetIndex(), Carry);
}
}
