How to plot cubic spline

Question

0 个投票

I'm trying to plot my cubic spline at the end of my code. I figure out how to get the data point needed to plot, but I can't figure out to get the graph to work.

My matrix with Y,B,C,D look like this

plotwo =

Columns 1 through 3

5.0000 1.0144 0

6.0000 0.9713 -0.0431

6.5000 -0.3995 -1.3278

5.5000 -0.8732 0.8541

5.5000 0.8923 0.9115

Column 4

-0.0144

-0.4282

0.7273

0.0191

-0.3038

This is what I tried the code always starts at x=1,2,3

xx=h;%x cords
for i=1:+1:d-1
    y=plotwo(i,1)+ plotwo(i,2)*(x-i)+plotwo(i,3)*((x-i)*(x-i))+plotwo(i,4)*((x-i)*(x-i)*(x-i));
    fplot(xx,y,'*');
    hold on
end