Splines matriz ampliada, código Matlab | Normal splines, Matlab code

t=0:2:18;

w=[1000 1400 1600 1690 1720 1760 1900 2150 2700 3000];

n=length(w);

A=[1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   1 2 4 8 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 1 2 4 8 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 1 4 16 64 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 1 4 16 64 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 1 6 36 216 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

   0 0 0 0 0 0 0 0 0 0 0 0 1 6 36 216 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 1 8 64 512 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 8 64 512 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 10 100 1000 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 10 100 1000 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 12 144 1728 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 12 144 1728 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 14 196 2744 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 14 196 2744 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 16 256 4096 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 16 256 4096;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 18 324 5832;

   0 1 4 12 0 -1 -4 -12 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 1 8 48 0 -1 -8 -48 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 1 12 108 0 -1 -12 -108 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 1 16 192 0 -1 -16 -192 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 20 300 0 -1 -20 -300 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 24 432 0 -1 -24 -432 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 28 588 0 -1 -28 -588 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 32 768 0 -1 -32 -768;

   0 0 2 12 0 0 -2 -12 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 2 24 0 0 -2 -24 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 2 36 0 0 -2 -36 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 48 0 0 -2 -48 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 60 0 0 -2 -60 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 72 0 0 -2 -72 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 84 0 0 -2 -84 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 96 0 0 -2 -96;

   0 0 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0;

   0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 108];

B=[1000; 1400; 1400; 1600; 1600; 1690; 1690; 1720; 1720; 1760; 1760; 1900; 1900; 2150; 2150; 2700; 2700; 3000; 0; 0; 0; 0; 0; 0; 0; 0; 0; 0; 0; 0; 0; 0; 0; 0; 0; 0];

v=inv(A)*B;

i=1;

plot(t,w,'o');

hold on

while i<=(n-1)

   a=v(4*i-3);

   b=v(4*i-2);

   c=v(4*i-1);

   d=v(4*i);

   x=(i-1)*2:0.01:2*i;

   y1=a+b*x+c*(x.^2)+d*(x.^3);

   plot(x,y1,'color',[rand,rand,rand]);

   i=i+1;

end