@ravindra

agree!

On Oct 24, 2:20 pm, ravindra patel <[email protected]> wrote:
> @ Kishen
> So lets say you have 100 parallel processors and you are given an array of
> 100 elements, then the loop will execute in 1 clock. Now lets say on the
> same machine you are given a problem array of 1 million elements. So how
> many clocks are you gonna consume, assuming all your 100 processors are
> running in parallel.
>
> Buddy, with parallel processors you can reduce total computation time at
> most by a factor of number of processors you have (which will always be a
> constant, no matter how big it is). It has nothing to do with time
> complexity.
>
> Thanks,
> - Ravindra
>
>
>
> On Fri, Oct 22, 2010 at 8:17 AM, Kishen Das <[email protected]> wrote:
> > Ok, if you look at the inner loop, it is -
>
> >  for ( j = i to j = 0 ) {
> >  sum[j] +=  A[ i]
> >  product[j] *= A [ i]
> > }
>
> > This is as good as executing -
> > sum[i] =   sum [ i ] + A[ i ] ---> ( 1 )
> > sum[i-1]= sum[i-1]+ A[i]  ----> ( 2 )
> > ----------
> > -----------
> > -----------
> > sum[0]  = sum[ 0]+A[i]   ------> ( i )
>
> > Each of these assignments doesn't have any dependency with other
> > computations i.e.,
> > ( 1 ) is independent of ( 2 ) to ( i ) and so does ( 2 ) , ( 3 ) , .... ( i
> > )
> > and hence each of this can be assigned to a different processor.
> > So, each of these statements( iterations) of the inner-loop j can be run in
> > different processors, making it O(1).
>
> > I am sorry, if people are still not getting my point !!!
> > This is the best I can do !!!
>
> > Kishen
>
> > On Thu, Oct 21, 2010 at 9:08 AM, ligerdave <[email protected]> wrote:
>
> >> @Kishen
>
> >> I don't have much knowledge on parallel computation in OpenCL or CUDA.
> >> Do you mean parallelised="not have to do the computation at all"?
> >> did you mean without knowing the boundary of the inner loop which is
> >> depended on the outer loop, the inner loop would be smart enough to
> >> figure out the i and j?
>
> >> On Oct 20, 7:33 pm, Kishen Das <[email protected]> wrote:
> >> > Well, looks like people are not understanding when I say "run a loop in
> >> > parallel "!!!
>
> >> > Please look at some of the examples on Nvidia website on how
> >> computations
> >> > can be parallelised in OpenCL or CUDA.
> >> > And also some of the high level programming languages like Scala which
> >> is
> >> > also providing these parallel constructs.
>
> >> > If you don't understand GPUs or not familiar with parallel constructs in
> >> > Java, then my algorithm will definitely look like O ( n ^ 2 ).
>
> >> > Kishen
>
> >> > On Wed, Oct 20, 2010 at 4:25 PM, ligerdave <[email protected]>
> >> wrote:
> >> > > @Kishen
> >> > > as long as you have one for loop in another, you wont have O(n). it
> >> > > will most likely run O(n^2)
>
> >> > > On Oct 19, 7:41 pm, Kishen Das <[email protected]> wrote:
> >> > > > In the below code the jth and kth inner for loops can be run in
> >> parallel
> >> > > > making them O(1) and the entire thing O(n).
>
> >> > > > for ( i=0 to i=N-1 )
> >> > > > {
>
> >> > > > for ( j = i to j = 0 ) {
> >> > > > sum[j] +=  A[ i]
> >> > > > product[j] *= A [ i]
>
> >> > > > }
>
> >> > > > for( k=0 to k= i )
> >> > > > if ( sum[k] == S and product[k] == P ) {
> >> > > > Answer is the sub array A[k to i ]
> >> > > > break
>
> >> > > > }
> >> > > > }
>
> >> > > > Kishen
>
> >> > > > On Tue, Oct 19, 2010 at 11:36 AM, abhishek singh <
> >> [email protected]
> >> > > >wrote:
>
> >> > > > > @ Rahul patil  ofcourse array may have negative or positive
> >> integers
>
> >> > > > > @ Kishen   both O(n) and O(n logn) solutions was asked in this
> >> yahoo
> >> > > coding
> >> > > > > round question
>
> >> > > > > On Tue, Oct 19, 2010 at 1:28 PM, Abhishek Kumar Singh <
> >> > > > > [email protected]> wrote:
>
> >> > > > >> Given an array of length N. How will you find the minimum length
> >> > > > >> contiguous sub - array of whose sum is S and whose product is P .
> >> Here
> >> > > > >> S and P will be given to you.
>
> >> > > > >> --
> >> > > > >> You received this message because you are subscribed to the
> >> Google
> >> > > Groups
> >> > > > >> "Algorithm Geeks" group.
> >> > > > >> To post to this group, send email to [email protected].
> >> > > > >> To unsubscribe from this group, send email to
> >> > > > >> [email protected]<algogeeks%2bunsubscr...@googlegroups
> >> > > > >>  .com>
> >> <algogeeks%2bunsubscr...@googlegroups .com>
> >> > > <algogeeks%2bunsubscr...@googlegroups .com>
> >> > > > >> .
> >> > > > >> For more options, visit this group at
> >> > > > >>http://groups.google.com/group/algogeeks?hl=en.
>
> >> > > > > --
> >> > > > > ABHISHEK KUMAR SINGH
> >> > > > > BTECH (INFORMATION TECHNOLOGY)
> >> > > > > IIIT ALLAHABAD
> >> > > > > 9956640538
>
> >> > > > > --
> >> > > > > You received this message because you are subscribed to the Google
> >> > > Groups
> >> > > > > "Algorithm Geeks" group.
> >> > > > > To post to this group, send email to [email protected].
> >> > > > > To unsubscribe from this group, send email to
> >> > > > > [email protected]<algogeeks%2bunsubscr...@googlegroups
> >> > > > >  .com>
> >> <algogeeks%2bunsubscr...@googlegroups .com>
> >> > > <algogeeks%2bunsubscr...@googlegroups .com>
> >> > > > > .
> >> > > > > For more options, visit this group at
> >> > > > >http://groups.google.com/group/algogeeks?hl=en.
>
> >> > > --
> >> > > You received this message because you are subscribed to the Google
> >> Groups
> >> > > "Algorithm Geeks" group.
> >> > > To post to this group, send email to [email protected].
> >> > > To unsubscribe from this group, send email to
> >> > > [email protected]<algogeeks%2bunsubscr...@googlegroups
> >> > >  .com>
> >> <algogeeks%2bunsubscr...@googlegroups .com>
> >> > > .
> >> > > For more options, visit this group at
> >> > >http://groups.google.com/group/algogeeks?hl=en.
>
> >> --
> >> You received this message because you are subscribed to the Google Groups
> >> "Algorithm Geeks" group.
> >> To post to this group, send email to [email protected].
> >> To unsubscribe from this group, send email to
> >> [email protected]<algogeeks%2bunsubscr...@googlegroups
> >>  .com>
> >> .
> >> For more options, visit this group at
> >>http://groups.google.com/group/algogeeks?hl=en.
>
> >  --
> > You received this message because you are subscribed to the Google Groups
> > "Algorithm Geeks" group.
> > To post to this group, send email to [email protected].
> > To unsubscribe from this group, send email to
> > [email protected]<algogeeks%2bunsubscr...@googlegroups 
> > .com>
> > .
> > For more options, visit this group at
> >http://groups.google.com/group/algogeeks?hl=en.

-- 
You received this message because you are subscribed to the Google Groups 
"Algorithm Geeks" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to 
[email protected].
For more options, visit this group at 
http://groups.google.com/group/algogeeks?hl=en.

Reply via email to