Re: [Gnuplot-info] Option reverse and table

[Loïc <xl...@fr...>]

Many thanks, I didn't think at a parametric curve.

Loïc

Le mercredi 23 juillet 2008 à 00:15 +0200, Hans-Bernhard Bröker a
écrit :
> Loïc wrote:
> 
> > set table "out" 
> > set xrange [0:10] reverse
> > plot x**2
> 
> [...]
> 
> > Hence, x are in increasing mode, and not decreasing as I wish.
> > 
> > Is it a bug ? 
> 
> No.  There's no promise of the range reversal affecting sampling order. 
>   It affects the relation between coordinates and positions on a graph, 
> not the order in which those positions are visited.  That ordering is 
> generally unimportant, since you couldn't spot the difference in the 
> resulting image anyway.
> 
> The table driver makes that a bit mor complicated, of course.  But, like 
> with so many problems, parametric mode helps:
> 
> gnuplot> set table ; set parametric ; set samples 15
> gnuplot> f_x(t) = 10 - t
> gnuplot> plot [0:10] f_x(t), f_x(t)**2
> 
> #Curve 0 of 1, 15 points
> #x y type
>   10  100  i
>   9.28571  86.2245  i
>   8.57143  73.4694  i
>   7.85714  61.7347  i
>   7.14286  51.0204  i
>   6.42857  41.3265  i
>   5.71429  32.6531  i
>   5  25  i
>   4.28571  18.3673  i
>   3.57143  12.7551  i
>   2.85714  8.16327  i
>   2.14286  4.59184  i
>   1.42857  2.04082  i
>   0.714286  0.510204  i
>   0  0  i
> 
>