diff --git a/samples/plot,functions,polyval.m b/samples/plot,functions,polyval.m
index bbb331d..a153998 100644
--- a/samples/plot,functions,polyval.m
+++ b/samples/plot,functions,polyval.m
@@ -1,10 +1,10 @@
 fplot( @(x) x^2 * cos(x), [-4 4],'r*' )
 hold on
 
-p= [1,2,3,4,5]
-x=1:0.1:10
+p= [1,2,3,4,5] //coefficinti del polinomio
+x=1:0.1:10  oppure x=linspace(-5,5,100) 100 punti tra -5,5
 y=polyval(p,x)
 plot(x,y)
 
 
-polyfit(x,y,n) // n è il grado
\ No newline at end of file
+p= polyfit(x,y,n) // n è il grado, 1 in meno dei punti
\ No newline at end of file