If you are using +/ and +/ .* on integers then you are using integers as cardinals, and
- You are stuck with 64-bit integers in J64 until the time (could be never) 32-bit integers are implemented in J64. - If the suite of functions you apply to integer mapped files is limited (e.g. just +/ and +/ .* and a few others), you could write a DLL that perform these functions. Other manipulations of 32-bit integers not as cardinals (e.g. reshape, take, drop, from) can be effected in J64 by mapping the file as a 4-column literal matrix. ----- Original Message ----- From: Anssi Seppälä <[EMAIL PROTECTED]> Date: Thursday, October 4, 2007 23:16 Subject: Re: [Jgeneral] Are 32bit integers in 64bit J possible? To: General forum <[email protected]> > For my purposes the +/ an +/ . * are superior functions with > mapped > files. I do not understand how I could use such decoding with > these in place? > > I is fine that there is a way to improve J if there is > commercial > demand for this feature in the future. > > Anssi > > At 18:05 4.10.2007, you wrote: > >Depending on how the integers are used you may > >have alternatives. > > > >If you are using integers as ordinals or codes, then use > >a literal matrix with a sufficient number of columns. e.g. > > > >- encoding the age in years of people: using a 1-column > >literal matrix (or a literal vector). > >- dates as day numbers from 1960-01-01: use a 2-column > >literal matrix (sufficient for about 180 years) > >etc. > > > >If not ordinals or codes, use a k-column literal matrix > >where k e. 1 2 4 to encode k-byte integers, and convert > >each time you need the numbers. > > > >You have to decide is whether the extra programming > >complications (or paying Jsoftware to implement 32-bit > >integers in J64) are worth the savings in RAM. > > > > > > > >----- Original Message ----- > >From: Roger Hui <[EMAIL PROTECTED]> > >Date: Thursday, October 4, 2007 1:13 > >Subject: Re: [Jgeneral] Are 32bit integers in 64bit J possible? > >To: General forum <[email protected]> > > > > > It is theoretically possible for J64 to have k-bit integers > > > where k e. 8 16 32 64. > > > > > > > > > ----- Original Message ----- > > > From: Anssi Seppälä <[EMAIL PROTECTED]> > > > Date: Thursday, October 4, 2007 0:44 > > > Subject: [Jgeneral] Are 32bit integers in 64bit J possible? > > > To: General forum <[email protected]> > > > > > > Is it (even in theory) possible that 64 bit J could have 32 bit > > > integers? The motivation is that integer mapped files of J64 > require> > double size compared to J32. 1,5 GB J32 mapped is > equivalent to 3 GB > > > J64 mapped file and the GBs of RAM have a price. ---------------------------------------------------------------------- For information about J forums see http://www.jsoftware.com/forums.htm
