Why do I receive 'Error using sym>tomupad' in Line 6 when plotting impulse signal with right time shifting?

%create symbolic functions x, a, b, c, d, e, f_c with independent variable t
syms x(t) a(t) h(t) b(t) c(t) d(t) e(t) f_c(t)
x(t) = cos(100*pi*t);
a(t) = x(0.4*t);
h(t) = stem([0]+0.02,[1]);
%plot signal x(t)
figure
fplot(x(t))
xlim([-0.5 0.5]),ylim([-2 2])
title ('Time domain of signal x(t)')
xlabel('Time, t')
ylabel('Amplitude, x(t)')
grid on
%plot signal h(t)
figure
fplot(h(t))
xlim([-0.5 0.5]),ylim([-2 2])
title ('Time domain of signal h(t)')
xlabel('Time, t')
ylabel('Amplitude, h(t)')
grid on

[TEOH CHEE JIN]

When writting in mathematical expression, h(t) = 𝛿(t-0.02). I expect the impulse signal to shift right by 0.02 seconds after plotting it.

Answer 1

[VBBV]

%create symbolic functions x, a, b, c, d, e, f_c with independent variable t
syms x(t) a(t) h(t) b(t) c(t) d(t) e(t) f_c(t)
x(t) = cos(100*pi*t);
a(t) = x(0.4*t);
h = stem([0]+0.02,[1])

h = 
  Stem with properties:

              Color: [0 0.4470 0.7410]
          LineStyle: '-'
          LineWidth: 0.5000
             Marker: 'o'
         MarkerSize: 6
    MarkerFaceColor: 'none'
          BaseValue: 0
              XData: 0.0200
              YData: 1

  Show all properties

%plot signal x(t)
figure
fplot(x(t))
xlim([-0.5 0.5]),ylim([-2 2])
title ('Time domain of signal x(t)')
xlabel('Time, t')
ylabel('Amplitude, x(t)')
grid on

%plot signal h(t)
% figure
% plot(h.XData,h.YData)
% % xlim([-0.5 0.5]),ylim([-2 2])
% title ('Time domain of signal h(t)')
% xlabel('Time, t')
% ylabel('Amplitude, h(t)')
% grid on

[VBBV]

h = stem([0]+0.02,[1])  % stem returns the function handle structure

You are trying to plot function handle using fplot. instead access XData , YData from function handle and plot