viewport/window edges

[Andrew Wittenberg <andyw@xxxxxxxxxxxxxxxxxxxx>]

Dear Ferreters,

I'm having trouble getting a viewport to fill the entire window area in
Ferret v5.22 for Linux.  "GO magnify" almost works, but for some reason
this gives small gaps at the right/top edges of windows with low/high
aspect ratios. The following demo distills my script and magnify.jnl down
to their basics (I think).  It makes a short, wide window and tries to
fill it with red shading.  (Beginners -- don't try this because it will
mess up your Ferret session.)

yes? set window/size=.05/aspect=.05 1                    ! setup window
yes? ppl origin 0 0; ppl axlen ($vp_width) ($vp_height)  ! "go magnify"
yes? shade/i=1:2/j=1:2/pal=red i*j                  ! fill the viewport 

Note the gap between the right edge of the viewport and the window. The
gap is absent when when the window aspect is near 1.  For wide windows
there's a gap on the right, and for tall windows there's a gap at the top.
Is this a PlotPlus bug or am I missing something? 

Thanks for any insights!

Andrew

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Andrew Wittenberg          Program in Atmospheric and Oceanic Sciences
andyw@splash.princeton.edu                        Princeton University
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