That sounds like a good idea.
Except I think we need three parameters:
list of names
disambiguating prefix
list of values
I think I'd like the list of names be x, the prefix be adverb argument and
the list of values be y.
So here's an implementation:
masgn=:1 :0
:
bad=.a.-.;'0Aa' ([ (+ i.) 1 + -~)&.(a.&i.)&.> '9Zz'
names=. ('_' I.@e.&bad@]} m&,)&.>x
(names [erase 'names bad x y')=: y
)
Example use:
(;:'a 1.1 b') 'z' masgn i.3 3
0 1 2
3 4 5
6 7 8
za
0 1 2
z1_1
3 4 5
zb
6 7 8
Of course I probably went a little overboard here with the implementation.
So feel free to strip out parts you don't need. And maybe add a 0 0$ at the
beginning of the result line, if you do not like results.
Thanks,
--
Raul
On Mon, May 26, 2014 at 4:39 AM, 'Pascal Jasmin' via Programming <
[email protected]> wrote:
> The way I would do it would be to add a prefix passed from x parameter,
> and replace spaces (or illegal characters ') with underscores. Assuming
> other illegal characters are rare should be fine, but the advantage of
> prefixing all columns helps both in preventing collisions with general J
> names, and allows processing multiple such files without collision.
>
>
> ----- Original Message -----
> From: Ric Sherlock <[email protected]>
> To: Programming JForum <[email protected]>
> Cc:
> Sent: Sunday, May 25, 2014 4:20:16 PM
> Subject: Re: [Jprogramming] Multiple assignments
>
> I recently released an update to addons/dsv that contains a new utitlity:
> assign2hdr
>
> testcsv=: noun define
> # The following is an example of a comma-separated file with
> # comment lines at the start of the file indicated by the fact they
>
> # start with the # symbol.
>
> id,bar code,name
>
> 24582621,119533,DELTOP DAVINCI
>
> 25422991,155439,AMBZED ROSCOE S2F
>
> 25784612,135624,TEF SHADOW BLARIS
>
> 22063188,102545,BIG P BLONDEL PRIM
>
> 20803506,137609,MONGA FLOL
>
> 27360900,107865,FRAMBIN R NOGN ET
>
> )
>
>
> fixcsv testcsv
>
> +--------+--------+------------------+
>
> |id |bar code|name |
>
> +--------+--------+------------------+
>
> |24582621|119533 |DELTOP DAVINCI |
>
> +--------+--------+------------------+
>
> |25422991|155439 |AMBZED ROSCOE S2F |
>
> +--------+--------+------------------+
>
> |25784612|135624 |TEF SHADOW BLARIS |
>
> +--------+--------+------------------+
>
> |22063188|102545 |BIG P BLONDEL PRIM|
>
> +--------+--------+------------------+
>
> |20803506|137609 |MONGA FLOL |
>
> +--------+--------+------------------+
>
> |27360900|107865 |FRAMBIN R NOGN ET |
>
> +--------+--------+------------------+
>
>
> assign2hdr fixcsv testcsv
>
> bar_code
>
> 119533 155439 135624 102545 137609 107865
>
>
> It does try to automatically coerce names, but does so by removing leading
> blanks and any leading chars that aren't valid starting chars for a name.
> Adding as 'X' in front may be better than that.
>
> On May 26, 2014 5:04 AM, "Devon McCormick" <[email protected]> wrote:
>
> > Assigning column names this way can be very useful. However, it requires
> > that column names be valid J variable names. The R programming language
> > has a feature like this that includes automatic coercion of invalid names
> > for at least a couple of simple cases - something like changing embedded
> > spaces to underscores and prefixing any name beginning with a numeral
> with
> > "X".
> >
> > It might be useful to publicize a simple set of conversions like this
> for J
> > names on the wiki so that there's at least a stab at standardization.
> >
> >
> > On Sun, May 25, 2014 at 12:58 PM, J. Patrick Harrington
> > <[email protected]>wrote:
> >
> > > I've always liked this economy of assignment:
> > > 'e f g'=. s=. >1 2;3 4;5 6
> > > f
> > > 3 4
> > > e
> > > 1 2
> > > -- but I wondered if it were possible to extend this where the left
> hand
> > > side is not explicit:
> > > abc=. 'a';'bb';'ccc'
> > > ┌─┬──┬───┐
> > > │a│bb│ccc│
> > > └─┴──┴───┘
> > > I found I could make a single assignment:
> > > (>1{abc)=. 1{s
> > > bb
> > > 3 4
> > > a
> > > |value error: a
> > > But I didn't want to put this into a loop.
> > > It was neat to find that I could write:
> > > (abc)=. s
> > > a
> > > 1 2
> > > bb
> > > 3 4
> > > ccc
> > > 4 5
> > > abc
> > > ┌─┬──┬───┐
> > > │a│bb│ccc│
> > > └─┴──┴───┘
> > > This is useful in working with data files output
> > > by a stellar evolution program where I have ASCII tables with 90
> columns
> > > and over 1000 rows, and each
> > > column has a name 1 to 25 characters long: I wanted
> > > to read this into a J session, assigning the column
> > > values to each of the respective names. Turns out it
> > > can be done with one line of the form
> > > (head)=: data_array
> > > where
> > > head
> > > ┌────┬────┬──────┬────┬────┬──────────┬────────┬────────────
> > > ─────────────┬───────────────────┬─
> > > │zone│logT│logRho│logP│logR│luminosity│eps_grav│log_abs_
> > > eps_grav_dm_div_L│signed_log_eps_grav│..
> > > └────┴────┴──────┴────┴────┴──────────┴────────┴────────────
> > > ─────────────┴───────────────────┴─
> > > (see http://www.astro.umd.edu/~jph/mesa_read.ijs) Another example of
> the
> > > "black hole of J".
> > >
> > > I don't know where in the documentation this can be
> > > found - I just got there by experimentation.
> > >
> > > Patrick
> > >
> > > P.S. This started as a post asking for
> > > help in getting rid of a loop, but
> > > I found the solution along the way.
> > > ----------------------------------------------------------------------
> > > For information about J forums see http://www.jsoftware.com/forums.htm
> >
> >
> >
> >
> > --
> > Devon McCormick, CFA
>
>
>
> > ----------------------------------------------------------------------
> > For information about J forums see http://www.jsoftware.com/forums.htm
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
>
----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm
