[ferret_users] Re: How does the noaxis qualifier work?

[Ryo Furue <furue@xxxxxxxxxx>]

Hi Ansley,

Thank you for your response.

| What should happen is that axes are always plotted only on the first
| plot, never on an overlay plot. So, once you've said /noaxes you
| should not get axes on an /overlay plot.

I see. That makes sense.

| Another option is to use the trick with overlapping a second
| viewport on the first. Here's a message with an example that shows
| how to do that.
| 
| http://ferret.pmel.noaa.gov/Ferret/Mail_Archives/fu_2003/msg00444.html

Yes, this solves my problem!  Here I summarize a solution that
extends the approach described in the message cited above.

Goal:  Plot the axes as late as possible.

Solution:
  set data levitus_climatology
  def view/orig=0,0/clip=1,1 voverlay  ! same size as "full"

  set view full
  fill/k=1/hlimits=120:290/noaxes/nolabel temp !<-- no axes

  message

  set view voverlay
  contour/hlimits=120:290:10/k=1 temp

Why do I want to do this?

1) Axes are plotted over and over again as you add normal overlays.
As a result, when you edit a PostScript file generated by Ferret
and you want to edit some axis elements, you need to delete many
objects.

2) In one of my plots, a normal overlay plotted different numeric
labels on the axes over the ones plotted by previous commands:

  fill/. . .       !! plots the axes and numeric labels.
  contour/ov . . . !! plots the same axes and numeric labels.
  . . .
  contour/ov . . . !! plots DIFFERENT numeric labels and tics
                   !! marks over the original.

This may be a bug, which I can't reproduce in a simple case.

Finally, I found that even without overlays, axis elements are
plotted four times!  In a PostScript editor, I moved a numeric
label and found another beneath it.  I moved that one, revealing
yet another. . . .  Well, this isn't a serious issue at all,
but . . . .

Regards,
Ryo