@Sony. No. Consider the following table: rand5() (2/3)*rand5() _________________________ 1 0 2 1 3 2 4 2 5 3
Thus, (2/3)*rand5() is not uniformly distributed, nor is it in the range 0 to 2. Dave On Jul 31, 7:49 am, Sony Jose <sonyj...@gmail.com> wrote: > what about > > int i = rand5() + (2/3)*rand5(); > > won't this work? > > > > > > On Sat, Jul 31, 2010 at 5:46 PM, Dave <dave_and_da...@juno.com> wrote: > > Use the rejection method... > > > int rand7() > > { > > int i; > > do > > i = 5 * rand5() + rand5() - 3; > > while( i > 23 ); > > return i / 3; > > } > > > The loop assigns i a value between 5*1+1-3 = 3 and 5*5+5-3 = 27 with > > uniform probability, and then rejects any value of i > 23. Thus, after > > the loop, i has a uniform distribution on the interval 3 to 23. > > Dividing by 3 gives the desired result. > > > Under the assumptions of the problem, a value of i is rejected with > > probability 4/25, so the loop executes an average of 1/(1 - 4/25) = > > 25/21 times. Therefore, on average, it takes 50/21 rand5's to make a > > rand7. > > > Dave > > > On Jul 30, 8:33 am, jalaj jaiswal <jalaj.jaiswa...@gmail.com> wrote: > > > given a rand5 function which generates numbers from 1 to 5 with equal > > > probability.. give an algorithm which uses rand5 function and generates > > > numbers from 1 to 7 with equal probability > > > -- > > > With Regards, > > > Jalaj Jaiswal > > > +919026283397 > > > B.TECH IT > > > IIIT ALLAHABAD > > > -- > > You received this message because you are subscribed to the Google Groups > > "Algorithm Geeks" group. > > To post to this group, send email to algoge...@googlegroups.com. > > To unsubscribe from this group, send email to > > algogeeks+unsubscr...@googlegroups.com<algogeeks%2bunsubscr...@googlegroups.com> > > . > > For more options, visit this group at > >http://groups.google.com/group/algogeeks?hl=en. > > -- > Regards, > Sony- Hide quoted text - > > - Show quoted text - -- You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to algoge...@googlegroups.com. To unsubscribe from this group, send email to algogeeks+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.