clear all； clc

disp('插值求取平滑曲线后的数值' )

t = [5 10 15 20 30 40 60 80 120] ;

A = [29.84 40.01 46.71 53.87 63.32 67.01 67.33 67.54 67.87];

knots = 3; K = 3 ;          % 三次B样条

sp = spap2(knots,K,t,A);

pp = fnder(sp);         % 计算B样条函数的导函数

dAdt = fnval(pp,t);    % 计算t处的导函数值

rAm = dAdt;

% 绘制浓度拟合曲线

ti = linspace(t(1),t(end),200);

Ai = fnval(sp,ti);

plot(t,A,'ro',ti,Ai,'b:')

hold on

t = [5 10 15 20 30 40 60 80 120] ;

B = [36.32 48.21 55.81 62.21 69.81 72.39 72.72 72.91 73.92];

knots = 3; K = 3 ;          % 三次B样条

sp = spap2(knots,K,t,B);

pp = fnder(sp);         % 计算B样条函数的导函数

dBdt = fnval(pp,t);    % 计算t处的导函数值

rBm = dBdt;

ti = linspace(t(1),t(end),200);

Bi = fnval(sp,ti);

plot(t,B,'rx',ti,Bi,'b:')

hold on

t = [5 10 15 20 30 40 60 80 120] ;

C = [41.91 55.62 64.13 70.46 77.64 79.80 80.04 80.57 83.92];

knots = 3; K = 3 ;          % 三次B样条

sp = spap2(knots,K,t,C);

pp = fnder(sp);         % 计算B样条函数的导函数

dCdt = fnval(pp,t);    % 计算t处的导函数值

rCm = dCdt;

% 绘制浓度拟合曲线

ti = linspace(t(1),t(end),200);

Ci = fnval(sp,ti);

plot(t,C,'rs',ti,Ci,'b:')

hold on

t = [5 10 15 20 30 40 60 80 120] ;

D = [42.16 62.13 72.91 79.87 84.21 85.61 85.84 86.21 86.22];

knots = 3; K = 3 ;          % 三次B样条

sp = spap2(knots,K,t,D);

pp = fnder(sp);         % 计算B样条函数的导函数

dDdt = fnval(pp,t);    % 计算t处的导函数值

rDm = dDdt;

% 绘制浓度拟合曲线

ti = linspace(t(1),t(end),200);

Di = fnval(sp,ti);

plot(t,D,'rv',ti,Di,'b:')

Xlabel('t')

ylabel('X_A')

legend(o,'100%',x,'90%',s,'80%',v,'70%')