> I used the gnuplot code for long time. There is a request for your help.
> Could you tell me how write a Greek letter such as alpha or delta on
> the figure (x, y axises or a label)?
Depends on what terminal you use. In PostScript enhanced mode, you can
access the Symbol font; in TeX terminals, you can type \alpha, as usual.
I don't remember any other terminals supporting this.
Even if all the snow were burnt, ashes would remain.