Question: how to animate this plot

 support type error when plot, and moreover how to animate this plot

restart;
with(ExcelTools):
with(ListTools):
with(DynamicSystems):
filename := "0257.HK";
open3 := Import(cat(cat("C://Temp//HK//Bank//",filename),".xls"), filename, "B2:B100");
high3 := Import(cat(cat("C://Temp//HK//Bank//",filename),".xls"), filename, "C2:C100");
low3 := Import(cat(cat("C://Temp//HK//Bank//",filename),".xls"), filename, "D2:D100");
close3 := Import(cat(cat("C://Temp//HK//Bank//",filename),".xls"), filename, "E2:E100");
with(CurveFitting):
n := 31;
f := Vector(n);
f2 := Vector(n);
open2 := Vector(n);high2 := Vector(n);gain2 := Vector(n);algebra2 := Vector(n);creative2 := Vector(n);creative3 := Vector(n);
upper2 := Vector(n);lower2 := Vector(n);upperloweratio := Vector(n);
deltaopen2 := Vector(n); deltahigh2 := Vector(n); deltalow2 := Vector(n); deltaclose2 := Vector(n);
logn := Vector(n);
for i from 0 to n-4 do
open2[i+1] := PolynomialInterpolation([[0,open3[n-i][1]],[1,open3[n-(i+1)][1]],[2,open3[n-(i+2)][1]],[4,open3[n-(i+3)][1]]],t):
high2[i+1] := PolynomialInterpolation([[0,high3[n-i][1]],[1,high3[n-(i+1)][1]],[2,high3[n-(i+2)][1]],[4,high3[n-(i+3)][1]]],t):
low2[i+1] := PolynomialInterpolation([[0,low3[n-i][1]],[1,low3[n-(i+1)][1]],[2,low3[n-(i+2)][1]],[4,low3[n-(i+3)][1]]],t):
if (close3[i+1][1]/close3[i+2][1]-1) < 0 then
gain2[i+1] := -1*round(100*abs(close3[i+1][1]/close3[i+2][1]-1)):
else
gain2[i+1] := round(abs(100*(close3[i+1][1]/close3[i+2][1]-1))):
end if;
od;
n := 31;
newclose := Vector(n);
for j from 0 to n-4 do
for i from 0 to n-4 do
x1 := close3[i+1];
y1 := close3[i+1];
newclose[i+1] := subs(y=y1, subs(x=x1, (1/2)*(-y+sqrt(-3*y^2-4*y*x))/y))
od;
close3 := newclose;
plot(close3(x), x=1..31);
od;