PROGRAMA HECHO POR ALEX SANTOS QUISPE

function Grafico(x,y,a,b)

h=a:b;

n=length(h);

for i=1:n

j(i)=ejemplo(x,y,a);

a=a+1;

end

plot(h,j)

end

%x1=[1,2,5,6,7,8,10,13,17]

%y1=[3,3.7,3.9,4.2,5.7,6.6,7.1,6.7,4.5]

%x2=[17,20,23,24,25,27,27.7]

%y2=[4.5,7,6.1,5.6,5.8,5.2,4.1]

%x3=[27.7,28,29,30]

%y3=[4.1,4.3,4.1,3]

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function [s]=Spline(x,y,x0)

n=length(x);

for i=1:n-1

h(i)=x(i+1)-x(i);

end

%disp(h);

A(1,1)=1;

A(n,n)=1;

for i=2:n-1

A(i,i-1)=h(i-1);

A(i,i)=2*(h(i-1)+h(i));

A(i,i+1)=h(i);

end

%disp(A);

B(1)=0;

B(n)=0;

for i=1:n-2

B(i+1)=(3/h(i+1))*(y(i+2)-y(i+1))-(3/h(i))*(y(i+1)-y(i));

end

c=inv(A)*B';

for i=1:n-1

b(i)=(1/h(i))*(y(i+1)-y(i))-(h(i)/3)*(2*c(i)+c(i+1));

d(i)=(c(i+1)-c(i))/(3*h(i));

end

k=1;

for i=1:n-1

if(x0=x(i))

k=i;

end

end

if(x0>=x(n-1))

k=n-1;

end

end