AFAIK a.NotBits(b) means (a and not b):
a b result
0 0 0
0 1 0
1 0 1
1 1 0
Mattias
Thank you Mattias.
It works as you described.
Anyway, since ClearAll, AndBits, OrBits etc works iterating on
FBits : ^TBitArray;
they are much faster then the simple iteration along property
property Bits[Bit: longint]: Boolean read get write SetBit; default;
I think should be useful to have also at least two other methods
directly implemented in tbits:
1. the opposite of ClearAll, something like SetAll that sets all bits to
1, I think this s a typical operation on Bits;
procedure TBits.Setall;
var
loop : longint;
begin
for loop := 0 to FSize - 1 do
FBits^[loop] := 1;
end;
2. a Not operator, something like a.NotBits; with no arguments that
perform the not operation on the TBIts instance (a[i]:= not a[i]) or
something that performs a not operation on the passed TBits, i.e.
a.Not(b) that fills a in this way: a[i]:= not b[i];
procedure TBits.Notbits;
var
n : longint;
jj : cardinal;
loop : longint;
begin
for loop := 0 to FSize - 1 do
FBits^[loop] := not FBits^[loop];
end;
or
procedure TBits.Not(bitset : TBits);
var
n : longint;
loop : longint;
begin
if FSize < bitset.getFSize then
n := FSize - 1
else
n := bitset.getFSize - 1;
for loop := 0 to n do
FBits^[loop] := not bitset.FBits^[loop];
end;
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