I need to fix the code by using for loop to plot the relative error E in 2 norm versus n.

%%%% Taylor ploynomials pn(x)

x=2:0.01:3;
f = 1./x;
p1=1/2.5;
p2= 1/2.5 -(4/25)*(x-2.5);
p3= 1/2.5 -(4/25)*(x-2.5) + (8/125)*(x-2.5).^2;
p4= 1/2.5 -(4/25)*(x-2.5) + (8/125)*(x-2.5).^2 -(16/625)*(x-2.5).^3;

E1=sqrt((f-p1).^2)/sqrt((f).^2) 
E2=sqrt((f-p2).^2)/sqrt((f).^2)   
E3=sqrt((f-p3).^2)/sqrt((f).^2)
E4=sqrt((f-p4).^2)/sqrt((f).^2)

n=[1 2 3 4]
E=[ E1 E2 E3 E4];
semilogy(n,E)

[ebtisam almehmadi]

Plot I get looks acceptable but the code is wrong. Please Help

Answer 1

[Sivani Pentapati]

Please refer to the below code snippet to calculate the l2 norm of error in iterative way. For more information, please refer to for loop in MATLAB documentation.

p(1,:)=1/2.5;
for i=2:4
  
    p(i,:)= p(i-1,:)+ (4/25)*(2/5).^(i-2)*(-1).^(i-1)*(x-2.5).^(i-1);
  
end
E=sqrt((f-p).^2)/sqrt((f).^2);
n=1:4;
semilogy(n,E);