We should be able to concatenate boxed arrays with somewhat better performance. Conceptually speaking, the added box can be treated as an opaque string (other than reference counting bumps) for the purpose of the concatenation operation. Conceptually, also, already have some way of allocating memory in "power of two sized blocks". But memory management is a subtle thing, so maybe there is something I am missing?
Thanks, -- Raul On Mon, Mar 3, 2014 at 12:26 AM, bill lam <bbill....@gmail.com> wrote: > I would be quite happy if J can do that in a few minutes. The > bottle neck is not string related but J converts Json data into a > box array. Because concatenation of box arrays cannot be done > in place, it re-constructs a new box array for each node and this > is quadratic. > > Even if you can use python to parse json, it will still take a > quadratic operation to convert that parsed data structure > back to a J box array. Untested. > > Пн, 03 мар 2014, June Kim (김창준) писал(а): > > Hello, > > > > I recently tried to work on a JSON file (a bookmark file from Chrome > > browser), which is about 28MB. My initial attempt was using the json > parser > > from the J packages. Oh, it was slow. It took more than one minute on my > > machine. > > > > Disappointed, but I was kind of expecting the slow performance because > > string and tree are not what J's strength is. > > > > Now I turned to Python and tried parsing the file using the standard > > package. Oh, I took about a second. > > > > So I can proceed with Python but I want to know if there are any other > > options working with J with better performance. > > > > June > > ---------------------------------------------------------------------- > > For information about J forums see http://www.jsoftware.com/forums.htm > > -- > regards, > ==================================================== > GPG key 1024D/4434BAB3 2008-08-24 > gpg --keyserver subkeys.pgp.net --recv-keys 4434BAB3 > gpg --keyserver subkeys.pgp.net --armor --export 4434BAB3 > ---------------------------------------------------------------------- > For information about J forums see http://www.jsoftware.com/forums.htm > ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
