TSpIterator = class (TObject)
private
NextIndexes, PrevIndexes: array of Integer;
public
property Count: Integer read FCount;
property Current: Integer read FCurrent;
constructor Create(InitCount: Integer);
destructor Destroy; override;
procedure Next;
procedure Reset(NewInitCount: Integer); overload;
procedure Reset; overload;
end;
TSpTransMatrix = class (TSparseMatrix)
private
procedure SolveDegeneration(ARow, ACol: Integer);
public
constructor Create(InitRows, InitCols: Integer; ANullValue: Variant); override;
procedure BuildFBFSVogelsApprox( const Supplies: TSupplies;
const Demands: TDemands;
const Costs: TCostsMatrix);
end;
// TSpIterator
constructor TSpIterator.Create(InitCount: Integer);
begin
if ( InitCount > 0 )
then try
inherited Create;
Reset(InitCount);
except
on E: EOutOfMemory do
MessageDlg(E.Message, mtError, [mbOk], 0);
end
else Free;
end;
procedure TSpIterator.Reset(NewInitCount: Integer);
begin
FCount := NewInitCount;
SetLength(NextIndexes, NewInitCount);
SetLength(PrevIndexes, NewInitCount);
Reset;
end;
procedure TSpIterator.Reset;
var
i: Integer;
begin
FCount := Length(NextIndexes);
for i := 0 to (Count - 1) do begin
NextIndexes[i] := i + 1;
PrevIndexes[i] := i - 1;
end;
FirstIndex := 0;
LastIndex := Length(NextIndexes) - 1;
end;
destructor TSpIterator.Destroy;
begin
Finalize(NextIndexes);
Finalize(PrevIndexes);
inherited Destroy;
end;
// TSpTransMatrix
procedure TSpTransMatrix.BuildFBFSVogelsApprox( const Supplies: TSupplies;
const Demands: TDemands;
const Costs: TCostsMatrix);
var
TempDemands: TDemands;
TempSupplies: TSupplies;
RmcIndex, CmcIndex: Integer;
RowsLeft, ColsLeft: TSpIterator;
MinCost, SecMinCost, TempCost, MaxPenalty: Double;
SumCheck, Diff: Double;
i, j, mxpIndex, mxpMinCostIndex: Integer;
mxpIndexOf: (mxpioRow, mxpioCol, mxpioNone);
begin
if ( (Length(Supplies) <> Rows) or (Length(Demands) <> Cols) )
then Exit;
Clear;
SumCheck := 0;
SetLength(TempDemands, Cols); // Cols=6
SetLength(TempSupplies, Rows); // Rows=5 in the test data.
RowsLeft := TSpIterator.Create(Rows); // problem starts here
ColsLeft := TSpIterator.Create(Cols);
while ( SumCheck <> 0 ) do begin
// none of the code here reserves or releases any memory inside or
// outside the SpIterators.
// should I show it too?
end; // ( sumcheck <> 0 )
Finalize(TempSupplies);
Finalize(TempDemands);
ColsLeft.Free;
RowsLeft.Free;
end;
On Mon, 13 Nov 2000, Juan Manuel Gomez Ramos wrote:
> Hi there:
>
> I'm having a strange situation. I create, in a class method, two instances of
> another class. At the end of the method code, I call the Free method for both
> of them and, the one that was created the second, raises an
> EInvalidPointer exception. The weird thing I see, is that after they are
> created, both class variables have the same memory address (@Variable, this
> is the horrible part). And, if I Free them right after creation, no exception
> is raised (this, is the incredible part). I traced through the Destroy method
> and every code line was executed correctly (some open arrays are Finalized),
> except for the last one (no matter the operation), where the exception is
> raised. If the problem occurs while accessing a pointer already disposed off,
> then the exception should be raised on the second Free call but, it happend on
> the class instance created the second, no matter if is freed the first. Every
> thing goes ok while using the instances and their values keep different. I
> wouldn't like to use the "bad practice" of letting them unreleased. Thanks in
> advance.
>
> Best regards, JM.
>
> --
> Juan Manuel Gomez Ramos
> Computer Science student at Havana University
> Paraglider pilot and RadioHam (CM9BPG)
> http://cubairsports.itgo.com = http://www.geocities.com/cubairsports
>
> email:<[EMAIL PROTECTED]> eFax: +1-707-313-0329 (USA)
> <[EMAIL PROTECTED]> +44-870-125-4936 (UK)
> <[EMAIL PROTECTED]>
> ICQ: 62091995
> http://chronos.itgo.com
>
>
> ---------------------------------------------------------------------------
> New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED]
> Website: http://www.delphi.org.nz
> To UnSub, send email to: [EMAIL PROTECTED]
> with body of "unsubscribe delphi"
--
Juan Manuel Gomez Ramos
Computer Science student at Havana University
Paraglider pilot and RadioHam (CM9BPG)
http://cubairsports.itgo.com = http://www.geocities.com/cubairsports
email:<[EMAIL PROTECTED]> eFax: +1-707-313-0329 (USA)
<[EMAIL PROTECTED]> +44-870-125-4936 (UK)
<[EMAIL PROTECTED]>
ICQ: 62091995
http://chronos.itgo.com
---------------------------------------------------------------------------
New Zealand Delphi Users group - Delphi List - [EMAIL PROTECTED]
Website: http://www.delphi.org.nz
To UnSub, send email to: [EMAIL PROTECTED]
with body of "unsubscribe delphi"
