Using pointinterval to reduce points

Question

With pointinterval you can specify Gnuplot when you want to insert a point on a line. Now, setting this to -1, the line does not pass, although the point is. for instance

 pi -1 ----<>----<>----<>----<>----<>----<>----<>----<>----<>---- pi 2 ----<->----------<->----------<->----------<->----------<->---- 

As you can see, using values ​​other than -1 will insert a line inside the point.

I want to use positive pi to reduce the number of visible points, and at the same time I want to see that the line does not go through the point. Something like that

 ----<>----------<>----------<>----------<>----------<>---- 

How is this possible?

Answer 1

Just use a larger negative number like pi -5 :

 set xrange [0:1] plot '+' using 1:($1**2) pi -5 pt 6 lw 2 ps 1.5 w lp t 'pi -5', \ '+' using 1:($1**2 + 0.1) pi 5 pt 6 lw 2 ps 1.5 w lp t 'pi 5'