Re: gnuplot 4.1 and imagesc

[Daniel J S. <dan...@ie...>]

Seeing Ethan's email reminded me that an email I sent a while back didn't=
 get through the list:

Timoth=E9e Lecomte wrote:
> Here is a message from the octave mailing list kindly asking for a=20
> gnuplot release mainly for the image code.
> Any update on the remaining work, compared to Ethan's previous review ?=
=20
> Any domain where I could help, apart from stabilizing the wxWidgets=20
> terminal ?

Pick a bug in the list, I guess.  They seem to be coming in at a higher r=
ate lately... probably reflects increased usage.

Should keep a list of things to do on the gnuplot.info page.  In any case=
 I'll lobby for the following before a 4.2 release:

1)  BUG 1488168  	  z_floor and z_ceiling based on xyplane.absolute

There is a patch there to fix that one.  After applying this patch I sugg=
est also a change to the mouse behavior for the scale.  Have the xyplane =
move in the direction the mouse moves (i.e., invert the scale movement) a=
nd also have the motion be linear and not tend to zero as the xyplane nea=
rs zero.  If Ethan doesn't have time to change that and thinks it is wort=
h changing, I can modify that.


2)  BUG 1503114  	  FIX: 1107709 plot [-1:1] x is plotted with asymmetric=
 y-axis

I picked a bug in the list and fixed it.  It is a short little patch that=
 puts a 0.01 tolerance in computation of the tics before doing ceil() or =
floor().  That means an overrun of 1/100 of a tic will be ignored.  Not a=
 problem in most cases and if the user is concerned or even notices, manu=
al ranging can be done.

[I changed this recently from 1/100 of a tic to something like 1/200 of t=
he overall range in the "rounded outward" dimension.  This could use some=
 discussion on the list.  The concept is that in order to compensate for =
rounding errors--e.g., the tic interval is computed as 0.999999 and then =
after being used as the divisor causes ceil to grossly round upward---the=
 patch is ignoring 1/200 of the overall range.  It helps in cases of obvi=
ous mistakes, several of which appear in all.dem; much nicer.  The proble=
m might be for users whose data goes from, say, -2.0 to 2.001 or somethin=
g.  Gnuplot will then default to -2.0 to 2.0.  There are alternate ways t=
o address this I guess...  Maybe rounding the tic interval computation fi=
rst before using it in the division is the correct thing to do.]


3)  PATCH 1494573  	  check number of variables for u.d. functions

This is a really nice patch that will verify that the number of variables=
 supplied to a defined function matches the number of variables when defi=
ned.  Pretty straightforward patch; it simply adds a record to the struct=
ure of the number of variables.

[I'd like to see this one in before 4.2 because it promotes good programm=
ing practice.  There are one or two subtle behavioral things that develop=
ers might not agree with, but it does wait until the stage of evaluating =
to complain.]


4)  PATCH 1499728  	  revamped stat.inc

Crosses the t's and dots the i's on the p.d.f./c.d.f. definitions in stat=
.inc.  Also adds a bit of variety to 'prob.dem' making it more tutorial i=
n fashion.


5)  PATCH 1027032  	  Connect gnuplot_x11 to exterior application window

This one is of no urgency to me, but someone at some point requested it. =
 We're close on this one, and there was some detail left uncovered I can'=
t recall right now.  But it would be nice to add this one just to get it =
out of the patch list.


Dan