【1】用本章介绍的几种插值方法进行插值,间隔0.05
1.用interp1函数(四种方法)(函数调用格式:yi = interp1(x,y,xi,method))
x = [1,1.1,1.2,1.3,1.4];
y = [1.00000,1.23368,1.55271,1.99372,2.61170];
length_of_x = length(x);
scalar_x = [x(1):0.05:x(length_of_x)];
length_of_sx = length(scalar_x);
for i = 1:length_of_sx
y_nearest(i) = interp1(x,y,scalar_x(i),'nearest');
y_linear(i) = interp1(x,y,scalar_x(i),'linear');
y_spline(i) = interp1(x,y,scalar_x(i),'spline');
y_cubic(i) = interp1(x,y,scalar_x(i),'pchip');
end
subplot(2,2,1),plot(x,y,'*'),hold on,plot(scalar_x,y_linear),title('method=nearest');
subplot(2,2,2),plot(x,y,'*'),hold on,plot(scalar_x,y_spline),title('method=linear');
subplot(2,2,3),plot(x,y,'*'),hold on,plot(scalar_x,y_nearest),title('method=spline');
subplot(2,2,4),plot(x,y,