% B样条曲线生成实例

%  NUMERICAL METHODS: Matlab Programs
% (c) 2007 by Xie Liling
%  Complementary Software to accompany the textbook:
%  Information and Computing Science: A Laboratory Course

ctrlpoints=[0  -1.2  -1.6  -1.4  -1  -0.5  -0.35  -0.6  -1.6;
  -0.2  -0.5  -1  -1.5  -2.2  -2.7  -3.2  -3.7  -4.2];
knots=[0 0 0 0 1 2 3 4 5 6 6 6 6];
x0=ctrlpoints(1,:);
y0=ctrlpoints(2,:);
plot(x0,y0,'ro');%画所有控制点
hold on;
sp = spmak(knots,ctrlpoints);%生成B样条函数
fnplt(sp,[knots(1),knots(13)]);%根据所有节点，画样条曲线图

axis equal