function splines2(X,Y)
    for i=1:length(X)-1
        H(i)=X(i+1)-X(i);
        DY(i)=(Y(i+1)-Y(i))/H(i);
    end
    j=1;
    Matriz=zeros(length(H)-1,length(H)-1);
    for i=1:length(H)-1
        Matriz(i,j)=2*(H(i)+H(i+1));
        if i<>length(H)-1 then
          Matriz(i+1,j)=H(i+1);
          Matriz(i,j+1)=H(i+1);  
        end
        j=j+1;
        F(i)=6*(DY(i+1)-DY(i));
    end
    M=inv(Matriz)*F;
    M=[0,M',0];
    for i=1:length(X)-1
        disp("Coeficientes Pol. " + string(i))
        for j=3:-1:0
            disp(coeficiente(j,i,M,H,DY,Y))
        end
    end    
endfunction

function c=coeficiente(a,i,M,H,   DY,Y)
    switch a
    case 0
        c=Y(i);
    case 1
        c=DY(i)-(M(i+1)+2*M(i))/6*H(i)
    case 2
        c=M(i)/2
    case 3
        c=(M(i+1)-M(i))/(6*H(i));
    end 
endfunction