clear
!
x = [0;1;2;3;5;6;4;3;5;10]
y = 2*x^2-3*x+50 + 100*ran(x)
!
window 0
defaults
set
 plotsymbol -10
 plotsymbolcolor red
  
graph x y
set
 plotsymbol 0
 tension 0
 curvecolor blue

m = splsmooth(x,y,100)
graph\overlay m[*,1] m[*,2]
set
 textinteractive 0
 textalign 1
 %xtextlocation 15
 %ytextlocation 80
 %textheight 6
 textcolor blue

text 'tension = 0'
set
 tension 0.01
 curvecolor lime

m = splsmooth(x,y,100)
graph\overlay m[*,1] m[*,2]
set
 %ytextlocation 70
 textcolor lime

text 'tension = 0.01'
replot