Comments on: Even numbers as sum of 2 primes http://mariusbancila.ro/blog/2008/10/22/even-numbers-as-sum-of-2-primes/ Sharing my opinions and ideas! Tue, 10 Apr 2012 13:37:05 +0000 hourly 1 http://wordpress.org/?v=3.3.1 By: Ghita http://mariusbancila.ro/blog/2008/10/22/even-numbers-as-sum-of-2-primes/comment-page-1/#comment-28156 Ghita Tue, 09 Jun 2009 16:53:47 +0000 http://mariusbancila.ro/blog/?p=136#comment-28156 Discovered an issue related to memmory consumption here. The problem is that [ 1 .. n/2] is an array and not a sequence -> eats up more memory than needed for our problem: { 1 .. n/2 } should fix it Discovered an issue related to memmory consumption here. The problem is that [ 1 .. n/2] is an array and not a sequence -> eats up more memory than needed for our problem: { 1 .. n/2 } should fix it

]]> By: Ghita http://mariusbancila.ro/blog/2008/10/22/even-numbers-as-sum-of-2-primes/comment-page-1/#comment-28123 Ghita Mon, 08 Jun 2009 15:58:03 +0000 http://mariusbancila.ro/blog/?p=136#comment-28123 This approach (using seq) is very memory intensive for big numbers. This is a pitty considering the flexibility offered by seq and the fact that is lazy evaluated. Is there something that can be done on the same line so as to be able to apply the algorithm to bigger numbers (speed not a constraint) ? In a tipical imperative implementation the memory consumption would not be a constraint and it would be nice to see a functional approach here that works with bigger numbers also... BTW: great work ! This approach (using seq) is very memory intensive for big numbers. This is a pitty considering the flexibility offered by seq and the fact that is lazy evaluated. Is there something that can be done on the same line so as to be able to apply the algorithm to bigger numbers (speed not a constraint) ? In a tipical imperative implementation the memory consumption would not be a constraint and it would be nice to see a functional approach here that works with bigger numbers also…
BTW: great work !

]]> By: Carsten http://mariusbancila.ro/blog/2008/10/22/even-numbers-as-sum-of-2-primes/comment-page-1/#comment-18018 Carsten Thu, 23 Oct 2008 04:58:21 +0000 http://mariusbancila.ro/blog/?p=136#comment-18018 Hi, aside from optimizing by memoizing the primes (which would make this somewhat unreadable) you can improve performance if you not check all numbers from 2 to n/2 but only numbers from 2 to sqrt(n) in your prim-tester. Hi,

aside from optimizing by memoizing the primes (which would make this somewhat unreadable) you can improve performance if you not check all numbers from 2 to n/2 but only numbers from 2 to sqrt(n) in your prim-tester.

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