I guess you hit out of memory error becuase you did not raise sessin memory limit. Memory limit is read and set by 9!:20 and 9!:21 . it can also set in '~config/base.cfg' in j701 or config in j602 ide.
whether using jmf or not will not make it run in less ram. Anyways it will start disk swapping as soon as there is not enough phyiscal memory available. Втр, 08 Май 2012, Joe Bohart писал(а): > Hi J'ers, > > I'm trying to perform calculations on massive data sets using mapped files > and after searching the forum/essays am stuck. > > I've load 50 million integer digits of pi and trying to do a moving average > on them. I 've created two mapped files one for the data and one for the > calculated results, but I get out of memory errors. I'm not seeing what I'm > doing wrong here. > > My goal is to work with floating point numbers eventually, but i'd figure > i'd start with integers first, since there are more examples for integers > than floats in the 'mapped files' Labs (if anyone has the code for the > example mention in the 67 of 68 slide of the Lab on mapped files using NYSE > stock prices - I'd love to see it). > > load 'jmf files dir' > NB. data from http://zenwerx.com/projects/pi-digits/pi/ > NB. used perl to write each digits on 1 line of file data > pidata =: fread '/home/joe/pi-study/data' > NB. type is 2 (literal) > 3!:0 pidata > NB. convert to 4-byte integers > piInt =: _2 (3!:4) pidata > NB. shape is 50,000,000 > $piInt > ]sz=:7!:5 <'piInt' > NB. define moving average > ma =: mean \ > NB. out of memory ma, expected since storing results in ram > smoothPi =: 100 ma piInt > > NB. create jmf for results > fn =: jpath '~temp/pi-results.jmf' > ]sz=: 7!:5 <'piInt' > createjmf_jmf_ fn;sz > JFL map_jmf_ 'piResults'; fn > piResults =. 100 ma piInt > NB. still get out of memory! > > Much thanks ! > Joe > ---------------------------------------------------------------------- > 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 ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
