[SOLVED] weird Qrand behaviour

[doubitchou]

hi,
the use of recommanded qrand works nice when executed in PC or through the nokia simulator, but failed strangely to randomize when executed from the N8 itself.
Clearly : A function return a randomized QList, whereas the same function return an ordered QList each time.

I really don't see what is wrong here.

@
QList <int> Keys_Dialog::RandomKeys ()
{
QList <int> Keys_Set ;
QList <int> RemainingList ;

int MAX_KEYS_NB = 10                 ;           // define the max nr of keys to generate
int RandomValue = 0,  nb_val         ;


nb_val = Keys_Set.count()            ;
for (int i=0; i < MAX_KEYS_NB; i ++)
{
       RemainingList.append (i)      ;
}

while( RemainingList.count () > 0)
{
  RandomValue = (int) (((long) qrand() * RemainingList.count())/ RAND_MAX)  ;

      Keys_Set.append (RemainingList.at(RandomValue))                           ;
      RemainingList.removeAt (RandomValue);
      nb_val = Keys_Set.count()       ;

qDebug() << "Keys_Dialog::RandomKeys : " << Keys_Set ;
}

return Keys_Set                       ;

}@

[luca.cossaro]

Hi,

I've not tested, but I think this

@RandomValue = (int) (((long) qrand() * RemainingList.count())/ RAND_MAX);@

is always 0

[doubitchou]

Correct !

This was due to a bad init of the random generator that is lower in the the mobile.

thx a lot.