[Jprogramming] Bug/annoyances in plot

[Joey K Tuttle]

I was working with a friend on some curve fitting things and we were 
plotting the results along with a single point that represented the 
center of a circular fitting function. When trying to plot the single 
point, we ran into this -

iMi7:~ jkt$ j64
    JVERSION
Engine: j701/2011-01-10/11:25 build: Feb  6 2011 16:16:29
Library: 7.01.071
Platform: Darwin 64
Installer: j701a_mac64.dmg

InstallPath: /Applications/j64-701
    load 'plot'
    pd 'type point'
    pd 2;2
    pd 'show'
|length error: pdf_circle
|   'x y r'    =.y

Doing the same thing, but using

    pd (,2); ,2

worked as I expected, putting a single point at 2,2

I guess it is a bit unusual to want to plot a single point, but I think 
it should work with scalars the same as with length 1 vectors...

Trying to poke at this a bit more, I tried -

iMi7:~ jkt$ j64
    load 'plot'
    pd i.5
    pd 'show'
    pd 'type point'
    pd 2;3 4
    pd 'show'

and that seemed to work, apparently extending the scalar 2 to be 2 2 
BUT it also reverted the type on the line drawn by the pd i.5 to points, 
that seems unexpected/wrong too.

Doing a similar experiment on iOS (iPad) didn't get the length error, 
but did revert the line from pd i.5 to points after setting type point 
and doing pd 2;3.