Harvey - we covered something like this at the first NYCJUG meeting this
year, so I finally got around to putting up some wiki material on this in
response to your query: http://www.jsoftware.com/jwiki/NYCJUG/2008-01-08 .
Maybe this will be helpful.

Regards,

Devon

On Sat, Dec 27, 2008 at 1:23 PM, Hamish Harvey <[email protected]>wrote:

> Hello again,
>
> I was asking a while ago about placing text on a plot at positions
> specified in "graph coordinates". The example I gave wasn't very
> useful. My novice tacit expressions are probably more complex than
> they need to be, and I didn't give you any sample data. Sorry. I was a
> bit too lost in my own problems to see the obvious simplification,
> identical in all important respects, which is as follows.
>
> Consider the following simple plot:
>
>   X =. 0 1 2 3
>   Y =. 3 2 1 0
>   pd 'reset'
>   pd 'type dot'
>   pd X;Y
>   pd 'show'
>
> Given a list of boxed strings T with the same number of elements as X and
> Y:
>
>  T =. 'label1';'label2';'label3';'label4'
>
> I would like to draw those strings on the plot at the coordinates
> given by X and Y, such that they label the dots that the above snippet
> plots. Is this possible?
>
> I looked into getting the plot geometry from the locale variables Gx
> etc, but I think these are only assigned when "pd 'show'" is given.
>
> I've worked out I can get one character towards what I am after by
> using the "symbol" plot type, but I'd rather have a string located
> relative to the point in question, as a label rather than a marker.
>
> Thanks for any help,
> Hamish
>
> On Fri, Dec 5, 2008 at 22:59, Hamish Harvey <[email protected]>
> wrote:
> > Thanks Björn, but I'm afraid I don't follow. Sorry if I'm missing
> > something obvious.
> >
> > What I have is this:
> >
> > data =. ((1.5e8 * i. 5) ; 0 8 12 14 14) ,: (1.6e8 * i. 5) ; 0 9 14 16 16
> > coords =. (>./&>@:{.@:] , >./&>@:{:@:])"1 data
> > labels =. 'label 1'; 'label 2'
> > pd 'reset'
> > pd"1 data
> > pd"1 (<. 1000 * 7e8 18 %~"(1) 0.25e8 1 +"1 coords) ('text ', ":@:[ , '
> > '&,@:>@:])"(1 0) labels
> > pd 'show'
> >
> > The "coords" line finds the end point of each line in "data". The
> > second from last line then constructs a string 'text x y label',
> > taking labels from "labels" and coords from "coords", but adjusting
> > the coordinates approximately to match the graph axis coordinate
> > system. The scale and offset I judged by eye. Is there any way I write
> > text directly in the axis coordinate system, or obtain the
> > transformation data from pd?
> >
> > Cheers,
> > Hamish
> >
> > On Fri, Dec 5, 2008 at 21:21, Björn Helgason <[email protected]> wrote:
> >> http://www.jsoftware.com/svn/base/tags/j602a/plot/base/main/test1.ijs
> >>
> >> 2008/12/5 Hamish Harvey <[email protected]>
> >>
> >>> Hello,
> >>>
> >>> I'm enjoying getting to grips with J.
> >>>
> >>> I've just got to plotting some results, and I wonder if it is possible
> >>> to draw text using pd at graph coordinates. The options seem to be in
> >>> pixel or [0,1000] coordinate systems, both of which cover the full
> >>> area of the window (or pdf bounding box). I want to label the end of
> >>> plot lines, though.
> >>>
> >>> If not, is there any way to obtain the transformation from plot area
> >>> coordinates to one of these other systems?
> >>>
> >>> As an example: I have a line on a plot that ends at, say, (1.3e7, 45),
> >>> and want to place a label close to the end of that line.
> >>>
> >>> Thanks,
> >>> Hamish
> >>>
> >>> --
> >>> Hamish Harvey
> >>> Research Associate, School of Civil Engineering and Geosciences,
> >>> Newcastle University
> >>> ----------------------------------------------------------------------
> >>> For information about J forums see http://www.jsoftware.com/forums.htm
> >>>
> >>
> >>
> >>
> >> --
> >> Björn Helgason, Verkfræðingur
> >> Fugl&Fiskur ehf,
> >> Þerneyjarsundi 23, Hraunborgum
> >> Po Box 127,801 Selfoss ,
> >> t-póst: [email protected]
> >> gsm: +3546985532
> >> Landslags og skrúðgarðagerð, gröfuþjónusta
> >> http://groups.google.com/group/J-Programming
> >>
> >>
> >> Tæknikunnátta höndlar hið flókna, sköpunargáfa er meistari
> einfaldleikans
> >>
> >> góður kennari getur stigið á tær án þess að glansinn fari af skónum
> >>         /|_      .-----------------------------------.
> >>        ,'  .\  /  | Með léttri lund verður        |
> >>    ,--'    _,'   | Dagurinn í dag                     |
> >>   /       /       | Enn betri en gærdagurinn  |
> >>  (   -.  |        `-----------------------------------'
> >>  |     ) |        (\_ _/)
> >>  (`-.  '--.)       (='.'=)
> >>  `. )----'        (")_(")
> >>
> >> ----------------------------------------------------------------------
> >> For information about J forums see http://www.jsoftware.com/forums.htm
> >>
> >
> >
> >
> > --
> > Hamish Harvey
> > Research Associate, School of Civil Engineering and Geosciences,
> > Newcastle University
> >
>
>
>
> --
> Hamish Harvey
> Research Associate, School of Civil Engineering and Geosciences,
> Newcastle University
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
>



-- 
Devon McCormick, CFA
^me^ at acm.
org is my
preferred e-mail
----------------------------------------------------------------------
For information about J forums see http://www.jsoftware.com/forums.htm

Reply via email to