Please discuss [Re: [PATCH] boxplot: fix tics placement]

[Ethan A M. <sf...@us...>]

On Saturday, 03 January, 2015 12:39:14 Jouke Witteveen wrote:
> The x-value of individual boxplots is ignored when placing tics for
> multiple boxplots.
> 
> This patch fixes that issue. 
 [snip]

Bug tracker item: https://sourceforge.net/p/gnuplot/bugs/1532/

Example problem case adapted from the Bug Tracker
(Example uses only a single point per boxplot)

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
$DATA << EOD
2   1
3   2
5   3
EOD

set style boxplot separation 0
plot 'data' using 1:2:(0):(strcol(1)) with boxplot
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

There is a conflict between applying the first using spec (column 1)
as a coordinate and applying the style parameter "separation".

Currently the numeric column 1 values win for placing the
boxplots themselves (a single point each in the example).
So there are plots at x=2, x=3, and x=5.

But the separation spec wins for placing the labels,
which means the numeric values in column 1 are ignored and
their string representations all placed as labels at x=2.

Documentation:
  "The first and third columns (x coordinate and width) are normally
   provided as constants rather than as data columns."

Question:
  Is it ever correct to provide a non-constant x coordinate as
  in the example?  How would the program deal with a mismatch
  between the x-coordinate (column 1) and the "discrete levels of
  of factor variable" in column 4?  That can't happen in the 
  example above because the same data column is used for both
  but that wouldn't normally be true.

In other words - is this really a bug?