Sorry for repeating the question so many times. I try to display the graph, but the marked part does not appear. Can you help me?
clc; clear all; close all;

fun =@(t) (1/200).*t.^2+(1/500).*exp(-0.2.*t)+5;
dgraph = @(point, dfda, t) dfda*t + (fun(point)-dfda*point);

est_point=150;
da=2;

dfda_true=(1/100).*(150)+(-0.2./500).*exp(-0.2.*(150));
dfda_forward = (fun(est_point+da)-fun(est_point))./da;
dfda_backforward=(fun(est_point)-fun(est_point-da))./da;
dfda_center=(fun(est_point+da)-fun(est_point-da))./(2.*da)

a=-50:0.01:150;

figure(1)
plot(a,fun(a),’k’); hold on;
plot(a, dgraph(est_point,dfda_true,a),’b’); hold on; %dosen’t work
plot(a, dgraph(est_point,dfda_center,a),’r’); hold on;Sorry for repeating the question so many times. I try to display the graph, but the marked part does not appear. Can you help me?
clc; clear all; close all;

fun =@(t) (1/200).*t.^2+(1/500).*exp(-0.2.*t)+5;
dgraph = @(point, dfda, t) dfda*t + (fun(point)-dfda*point);

est_point=150;
da=2;

dfda_true=(1/100).*(150)+(-0.2./500).*exp(-0.2.*(150));
dfda_forward = (fun(est_point+da)-fun(est_point))./da;
dfda_backforward=(fun(est_point)-fun(est_point-da))./da;
dfda_center=(fun(est_point+da)-fun(est_point-da))./(2.*da)

a=-50:0.01:150;

figure(1)
plot(a,fun(a),’k’); hold on;
plot(a, dgraph(est_point,dfda_true,a),’b’); hold on; %dosen’t work
plot(a, dgraph(est_point,dfda_center,a),’r’); hold on; Sorry for repeating the question so many times. I try to display the graph, but the marked part does not appear. Can you help me?
clc; clear all; close all;

fun =@(t) (1/200).*t.^2+(1/500).*exp(-0.2.*t)+5;
dgraph = @(point, dfda, t) dfda*t + (fun(point)-dfda*point);

est_point=150;
da=2;

dfda_true=(1/100).*(150)+(-0.2./500).*exp(-0.2.*(150));
dfda_forward = (fun(est_point+da)-fun(est_point))./da;
dfda_backforward=(fun(est_point)-fun(est_point-da))./da;
dfda_center=(fun(est_point+da)-fun(est_point-da))./(2.*da)

a=-50:0.01:150;

figure(1)
plot(a,fun(a),’k’); hold on;
plot(a, dgraph(est_point,dfda_true,a),’b’); hold on; %dosen’t work
plot(a, dgraph(est_point,dfda_center,a),’r’); hold on; graph, disply, matlab, function MATLAB Answers — New Questions

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