Qt-interest Archive, January 2008
Getting the current qrand seed value
Message 1 in thread
Hi Everybody,
I am converting Delphi code that effectively does the following:
save = current_rand_seed;
qsrand( new_value );
...
qrand();
...
qsrand( save );
In other words, the code wants a reproducible sequence of random values, without causing problems elsewhere. I'm checking whether this is actually required to be converted.
If it is required, how do I obtain the current seed value in Qt? I understand that this will only be for the current thread.
Thanks in advance,
Tony Rietwyk
--
[ signature omitted ]
Message 2 in thread
Tony Rietwyk wrote:
> Hi Everybody,
>
> I am converting Delphi code that effectively does the following:
>
> save = current_rand_seed;
> qsrand( new_value );
> ...
> qrand();
> ...
> qsrand( save );
>
> In other words, the code wants a reproducible sequence of random values, without causing problems elsewhere. I'm checking whether this is actually required to be converted.
>
> If it is required, how do I obtain the current seed value in Qt? I understand that this will only be for the current thread.
>
> Thanks in advance,
>
> Tony Rietwyk
>
> --
> To unsubscribe - send a mail to qt-interest-request@xxxxxxxxxxxxx with "unsubscribe" in the subject or the body.
> List archive and information: http://lists.trolltech.com/qt-interest/
>
>
>
Greetings,
Before anything else i want to clarify that Qt does not provide random
number generator functionality. The random number generator is provided
by standard c++ (stdlib.h). So you have to check out the c++
documentation to find out what exactly you need although I think that
srand() function will suit you.
Check out the tic tac toe example of qt assistant and the following link
for further information.
http://www.cplusplus.com/reference/clibrary/cstdlib/srand.html
Regards,
Iosif A. Osman
--
[ signature omitted ]
Message 3 in thread
> -----Original Message-----
> From: Iosif A. Osman [mailto:osman@xxxxxxxxxxxx]
> Sent: Wednesday, 2 January 2008 19:08
> To: qt-interest@xxxxxxxxxxxxx
> Subject: Re: Getting the current qrand seed value
>
>
> Tony Rietwyk wrote:
> > Hi Everybody,
> >
> > I am converting Delphi code that effectively does the following:
> >
> > save = current_rand_seed;
> > qsrand( new_value );
> > ...
> > qrand();
> > ...
> > qsrand( save );
> >
> > In other words, the code wants a reproducible sequence of
> random values, without causing problems elsewhere. I'm
> checking whether this is actually required to be converted.
> >
> > If it is required, how do I obtain the current seed value
> in Qt? I understand that this will only be for the current thread.
> >
> > Thanks in advance,
> >
> > Tony Rietwyk
> >
> > --
> > To unsubscribe - send a mail to
> qt-interest-request@xxxxxxxxxxxxx with "unsubscribe" in the
> subject or the body.
> > List archive and information:
> http://lists.trolltech.com/qt-interest/
> >
> >
> >
>
>
> Greetings,
>
> Before anything else i want to clarify that Qt does not
> provide random
> number generator functionality. The random number generator
> is provided
> by standard c++ (stdlib.h). So you have to check out the c++
> documentation to find out what exactly you need although I think that
> srand() function will suit you.
>
> Check out the tic tac toe example of qt assistant and the
> following link
> for further information.
> http://www.cplusplus.com/reference/clibrary/cstdlib/srand.html
>
> Regards,
> Iosif A. Osman
Hi Iosif,
Thanks for responding.
qrand and qsrand were added at version 4.2. I'm on 4.3.1. According to
Assistant, they provide thread-safe versions of the standard C routines that
you refer to. These only allow you to reset to the original compiled value -
by srand(1).
Regards,
--
[ signature omitted ]
Message 4 in thread
> Hi Iosif,
>
> Thanks for responding.
>
> qrand and qsrand were added at version 4.2. I'm on 4.3.1. According to
> Assistant, they provide thread-safe versions of the standard C routines that
> you refer to. These only allow you to reset to the original compiled value -
> by srand(1).
>
> Regards,
>
> --
> To unsubscribe - send a mail to qt-interest-request@xxxxxxxxxxxxx with "unsubscribe" in the subject or the body.
> List archive and information: http://lists.trolltech.com/qt-interest/
>
Hi Tony,
I apologise for the mistake and for the confusion i may have caused. I
am using an older version of qt.
Regards,
Iosif A. Osman
--
[ signature omitted ]
