Using Jmf is overkill. Also what are the advantages of jmf over 3!:1/3!:2
in this case?
On Thu, 2 Feb 2023 at 7:17 PM Ak O <akin...@gmail.com> wrote:
> load 'jmf'
> NB. Loads jmf facilities.
>
> testfile =: {2,\?50#75
>
> fn =: jpath 'C:\Users\skip\J904-user\temp\foo\testfile_name.jmf'
> NB. Links a covername to the file path.
> createjmf_jmf_ fn;(([:(*&8)#);testfile)
> NB. Create the container for your file.
> NB. -fn is your reference name
> NB. -(([:(*&8)#);testfile) allocates the size of yor fike in bytes
>
> map_jmf_ 'testfile_disk';fn
> NB. Maps the file to a noun 'testfile_disk'
> ] testfile_disk_jmf_ =: testfile
>
> unmap_jmf 'testfile_disk_jmf_'
> NB. Release mappings
> Or
> Exit 0
> Close session.
>
>
> New session.
>
> load 'jmf'
> fn =: jpath 'C:\Users\skip\J904-user\temp\foo\testfile_name.jmf'
> map_jmf_ 'testfile1';fn
> NB. Map file
> ] testfile1_jmf_
> NB. File loaded as noun 'testfile1_jmf_'
>
> Some potential benefits of the .jmf datatype:
> -Preserves header and shape information.
> -If you want to map you file as read only, use the following syntax
> map_jmf_ 'testfile1';fn;'';1
> -If you would like it to be copy-on-write use the following syntax
> map_jmf_ 'testfile1';fn;'';2
>
>
> Ak
>
> On Wed., Feb. 1, 2023, 21:48 'Skip Cave' via Programming, <
> programm...@jsoftware.com> wrote:
>
> > I have a boxed noun:
> >
> > ] testfile =: {2,\?15#50
> >
> >
> >
> ┌────┬─────┬─────┬─────┬─────┬─────┬────┬────┬────┬────┬─────┬────┬───┬────┐
> >
> > │9 21│21 47│47 37│37 13│13 33│33 20│20 4│4 49│49 6│6 25│25 33│33 9│9 6│6
> > 43│
> >
> >
> >
> └────┴─────┴─────┴─────┴─────┴─────┴────┴────┴────┴────┴─────┴────┴───┴────┘
> >
> >
> > I want to store it in the following location on my machine:
> >
> >
> > ]fn =. < 'C:\Users\skip\J904-user\temp'
> >
> > ┌────────────────────────────┐
> >
> > │C:\Users\skip\J904-user\temp│
> >
> > └────────────────────────────┘
> >
> > Then I will close that J session.
> >
> >
> > Later, I will start a new J session, and I want to read that saved file
> > into a noun called 'test1'
> >
> >
> > What is the J code for writing the noun into a file in the first session?
> >
> > What is the J code to read the file into a noun in the second session?
> >
> > Should I use 1!2 & 1!:1, or fwrite & fread, or something else?
> >
> >
> > Where in the J doc are these file operations and their tradeoffs
> described?
> >
> >
> > Skip
> >
> >
> > Skip Cave
> > Cave Consulting LLC
> > ----------------------------------------------------------------------
> > For information about J forums see http://www.jsoftware.com/forums.htm
> >
> ----------------------------------------------------------------------
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