newton infinitas

function infinitas(x,y,xb)

m(:,1)=x;

m(:,2)=y;

c=0;

r=zeros(length(x)-1,length(x)+1);

for i=3:length(x)+1

    c=c+1;

    for j=1:length(y)-c

        m(j,i)=y(j+1)-y(j);

    end

   y=m(:,i);

end

p(1)=1;

p1(1)=1;

c=length(x);

for i=1:length(x)-1

    for j=1:i

        p1(2)=-x(j);

        p=conv(p,p1);

    end

    k=1;

    in=c;

    ind2=1;

    while k<=length(p);   

         r(i,in)=p(ind2);

            k=k+1;

            in=in+1;

            ind2=ind2+1;

    end

    c=c-1;

    p=ones(1);

end

h=x(2)-x(1);

disp(m);

ind=1;

for i=1:length(x)+1

    for j=3:length(x)+1

         r(ind,i)=r(ind,i)*(m(1,j)/(fact(ind)*(h^ind)));

         ind=ind+1;

    end

    ind=1;

end

pol=zeros(1,length(x)+1);

for i=1:length(x)+1

    for j=1:length(x)-1

        pol(i)=pol(i)+r(j,i);

    end

end

pol(length(x)+1)=pol(length(x)+1)+m(1,2);

f=poli(pol,xb);

disp(r);

disp(pol);

disp(f);

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function s=poli(x,y)

s=0;

n=length(x);

for i=1:n

s=s+x(i)*y^(n-i);

end

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function f=fact(x)

f=1;

for i=1:x

f=f*i;

end