Re: discontinuity feature worthwhile?

[Daniel J S. <dan...@ie...>]

Hans-Bernhard Br=F6ker wrote:

>> The only problem is choosing the plot range and samples correctly so=20
>> that the discontinuity ends up being selected. =20
>=20
>=20
> No.  The problem is that tuning of equidistant sampling can typically=20
> only be done to match *one* discontinuity --- but there's no way of=20
> telling how many discontinuities a plotted function might have in the=20
> plotted range, or where they'll be.

I had in mind each subrange could be treated with the same number of poin=
ts and not get too elaborate.  If it is oversampling on one region, so be=
 it.  (In essence, pretty much the same behavior of the parametric mode e=
xample you give.)

>=20
>> OK, well, then here is something else that would make plotting=20
>> discontinuities a little nicer.  Say f(x) is defined as above
>>
>> f(x) =3D x<1?0:1/x
>>
>> and I were able to plot subranges in my plot
>>
>> plot [x=3D-1:1-epsilon] f(x) with lines lc rgb "red", [x=3D1+epsilon:4=
]=20
>> f(x) with lines lc rgb "red"
>=20
>=20
> You *are* able to do that, once you switch to parametric mode.
>=20
>     set parametric
>     set trange [0:1-epsilon]
>      x1(t)=3D-1+2*t
>     x2(t)=3D1+3*t
>     plot x1(t),f(x1(t)),   x2(t), f(x2(t))

Oh yeah, parametric mode.  (All the possibilities!)  I will include this =
for a couple examples then, thanks.

I still think

plot [-1:1-eps,1:3] pareto(x), [-1:4] cos(x)

would be nicer.  Granted, parametric works.

>=20
>> the plotting process 1-epsilon is basically cast to 1.0.  (BTW, why=20
>> does putting the range in the plot override the "set xrange [#,#]"=20
>> command? =20
>=20
>=20
> Because that's what _all_ optional elements of a 'plot' command do, in=20
> gnuplot: they override whatever the default for some property of the=20
> plot might be.  'with <style>' overrides 'set style function' or 'set=20
> style data', 'linetype <n>' overrides the colour, and a range overrides=
=20
> the corresponding 'set *range'.

Well, that was my line of thinking.  When I say

plot x ls 4, x**2

the line style of 4 applies *only* to the first graph.  It does not apply=
 to all the graphs on the plot.  But I guess since {xrange} is before all=
 the functions it could be argued it should apply to all functions.

Dan