gplot versus plot

[oxyopes]

Hello,
1st thanks for the last help. I'm wandering why gplot is deprecated.
I like gnuplot functionalities. If i want to loop a plotting procedure
to get a few data plotted with points i can do that with gnuplot,
but with the plot command i cannot say "with points", and using the
same character for all plots is not nice. Is there a way to do that?

By the way, why this code does not work?
                  y=@(x) x.^2 ; fplot ("y(x)",[1,5])

if this is working
                 fplot ("cos(x)",[1,5]) works?

Thanks in advance again ...