Re: [Gnuplot-info] is painting with corners2color working incorrectly for Y axis?

[Yury <yur...@gm...>]

Hi Norwid,

On 15/04/2024 13:29, Norwid Behrnd via 
gnuplot-info wrote:
> the "tiles" are equidistant along (x,y) and the color levels appear to me
> symmetric (like an axis C_\infty in molecular symmetry / point groups,
> perpendicular to the drawing plane) around the central tile with an offset,
> i.e. its centre is at (0.5,0.5) instead of exactly (0,0) you prefer.  I do
> not know how to shift the array of tiles to account for this.

Can't do that in Gnuplot, AFAIU. You get either 
4-corners average or one of the corners. You'd 
have to shift gridlines and labels instead.

> notice `set samples 8 ; set isosamples 8` is a rather "lucky combination" as
> e.g., `set samples 9 ; set isosamples 9` or `set samples 7 ; set isosamples 7`
> distort the symmetry of this intensity map which can be misleading.

That combination wasn't 'lucky' in the sense of 
'well guessed'.

I wanted just what's on screen (now), i.e. 
coloured-squares visualisation of discrete 
Gaussian distribution in 2d, centered on (0,0), 
with squares' centers representing gridlines.

Like for representing digital low pass filtering 
of rasters.

The problem is (is it a bug? a feature?) that 
'samples' setting if used by itself (without 
'isosamples') produces *asymmetrical* picture 
along X and Y axii, which shouldn't be the case, 
as whatever value 'isosamples' was set to, it 
should be (?) used for both axii.

Just guessing, looks like a case of 
non-propagation of generalised values to 
non-generalised ones in the program source.

Thank you for that 'contourfill' snippet, looks 
interesting. But for my ongoing projects I'll 
stick with what I know. :)

-Yury