> (dx was maybe not the right expression, it is more than an infinite dx...)
An infinitely *small* delta_x, to be even more precise. Which would
take an infinite amount of time to use, because there would be
infinitely many function evaluations to be done in any finite x range.
I hope you see where this is heading: it's simply impossible.
Quote:> which samplingrate is useful?
Whatever fits your bill. Anything larger than the horizontal
resolution of your output format (screen, paper, whatever) is usually
a complete waste of effort, though.
If you want a sample at exactly x==0, you have to manually adjust the
x range and 'set samples' to get one there. For demonstration, try:
set xrange [-10:10]
set samples 5
pause -1 'Look at plot, then press a key'
set samples 6
and see the difference.
Even if all the snow were burnt, ashes would remain.