Yes --
the conjuction explanation makes a lot more sense ...
The application of cutl a 'record' at a time becomes apparent before the
first line of code in cutl is executed.
load 'debug'
dbss 'cutl *:*'
dbr 1
','&cutl;._2 csvfile
|stop: cutl
| y=.y,x
|cutl[:0]
y
a,tkr,dt,s,td,l,cd,qu,pr,val,cst,ty,lgl,sgl,iq,iu,ix,qc,qp,st,dte,cq,qv,cmt
x
,
>From A+, I'm familiar with a function being applied to each element of an
entity.
What surprised me was that the code in cutl was being reinterpreted by the
J-interpreter for each element.
I guess that's because the the conjuction is applied to a defined function,
and not a primitive.
On Sun, Jan 8, 2012 at 5:06 PM, Ric Sherlock <tikk...@gmail.com> wrote:
> To be precise cutl is being "fed" csvfile one record at a time by the
> conjunction cut ( ;. ). ( cutl;._2 ) will chop its right argument into
> bits using the last item of the right argument (probably a line-feed)
> as the record delimiter (fret) and apply the verb u (in your case (
> ','&cutl ) to each of those records.
>
> http://www.jsoftware.com/docs/help701/dictionary/d331.htm
>
> On Mon, Jan 9, 2012 at 6:50 AM, Tom Szczesny <tav...@gmail.com> wrote:
> >
> > ',' &cutl;._2 csvfile
> >
> > I was amazed that cutl loops through csvfile one 'record' at a time,
> > as none of the 9 control structure patterns listed in the Primer were
> > evident.
> >
> >
> >
> > On Mon, Jan 2, 2012 at 12:44 PM, Joey K Tuttle <j...@qued.com> wrote:
> >
> >> I believe that there are a collection of csv related utilities in addons
> >> ( require 'csv' will make those available to you).
> >>
> >> However, for years I have used a simplistic verb to bring .csv files
> >> into a j session as a table of enclosed values -
> >>
> >> cutl =: 3 : 0
> >> :
> >> y =. y,x
> >> q =. y e.'"'
> >> qs =. ~:/\q
> >> }.^: ('"'&=@([:{.1:{.]))&.> (qs<y e.x) <;._2&((q<:qs)&#) y
> >> )
> >>
> >> tablecsv =: 3 : 0
> >> ',' tablecsv y NB. allows choosing an alternative delimiter
> >> :
> >> x &cutl;._2 y
> >> )
> >>
> >>
> >> On 2012/01/02 09:22 , Tom Szczesny wrote:
> >> > Some languages, like q, have a built-in command for reading, parsing,
> and
> >> > loading data from csv files:
> >> > t: ("SSDIDSSIFFFIS";enlist ",") 0: `:/home/tom/t.csv
> >> >
> >> > Other languages, like a+, do not, and the user needs to write a
> function
> >> to
> >> > read, parse and load data from csv files.
> >> >
> >> > > From a cursory review, it appears that j is in the a+ camp.
> >> > Please confirm that such a facility does not exist in j, before I
> start
> >> > writing my own.
> >> >
> >>
> >> ----------------------------------------------------------------------
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> >>
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