Matlab生成平滑曲线.x=[20 25 30 35 40 45 50];y=[71.0,73.0,75.1,76.5,78.1,78.8,79.

x=[20 25 30 35 40 45 50];
y=[71.0,73.0,75.1,76.5,78.1,78.8,79.0];
plot(x,y)
p=polyfit(x,y,2);
hold on
plot(x,polyval(p,x),'r')