plotting delta function in zero interpolation and decimation

clc;
close all;
clear all;
x1= [1 2 3 4 5];
L = 2;
n = linspace(0,4,100);
m =linspace(0,10);
h1 = dirac(n - m*L);
idx  = h1 == Inf;
h1(idx) = 1;
h2 = dirac(n-m/L);
idx  = h2 == Inf;
h2(idx) = 1;
figure (1);
subplot(1,2,1);
for i = 1:numel(n);
    for j = 1:numel(m);
        y1{i,j} = conv(x1,h1(i,j));
        plot(y1{i,j});
    end
end
subplot(1,2,2);
for i = 1:numel(n);
    for j = 1:numel(m);
        y2{i,j} = conv(x1,h2(i,j));
        plot(y2{i,j});
    end
end

Hi all, this is my code, and I want to plot like the picture result. They say "Index in position 1 exceeds array bounds (must not exceed 1)". Please help me, what is wrong in my code?

Answer 1

[Abolfazl Chaman Motlagh]

the problem you are adressing is that n and m are 1x100 vector each. so the term (n-m*L) is 1x100 array. and it means h1 and h2 are not 2D array. they are 1D array with size of 1x100. here's what you should do:

n = linspace(0,4,100);
m =linspace(0,10);
[n,m] = meshgrid(n,m);

after this the h1 and h2 become the array you want.

h1 = dirac(n - m*2); % L=2
size(h1)

ans = 1×2

100 100

but remember don't use n and m in number of iteration of loops any more because they are no longer vectors. use this:

for i=1:size(n,1)
    for j=1:size(m,1)

but i'm not sure you'll be okay after this. because i don't have any idea what are you doing in the plot section. maybe share your formula to think about that part too.

[Tu Nguyen]

Thank you so much, I figured it out