How can I write an FIR filter function
4 views (last 30 days)
Show older comments
Hi! I'm trying to write a function that performs FIR filtering without having to use the built-in function.
so I have this code at the moment.
function y = myFIR(x,h)
M = length(x);
L = length(h);
y = zeros(0,((M+L)-1));
for n = 1:M+1
for k = 1:L+1
Y1 = (h(k).*x(n-k));
y(n)= sum(Y1);
end
end
where (h) is an array consisting of the impulse response, (x) is an array consisting of the input sequence and (y) is a vector containing the filtered samples.
but I have been getting the error below;
Array indices must be positive integers or logical values.
Error in myFIR (line 7)
Y1 = (h(k).*x(n-k));
I have really tried everything I could but it just doesnt seem to go. I will really be glad if anyone can help figure out the problem.
Thank you.
2 Comments
KALYAN ACHARJYA
on 12 Feb 2019
Edited: KALYAN ACHARJYA
on 12 Feb 2019
Can you define x and h inputs, examples?
Answers (1)
KALYAN ACHARJYA
on 12 Feb 2019
Edited: KALYAN ACHARJYA
on 12 Feb 2019
My suggestion to avoid the error, In the loop, during first iterations when when n=1 and k=1, then following statement
Y1 = (h(k).*x(n-k));
x(n-k) becomes x(0), which is not allowed in indexing vectors. x(Positives only)
See Also
Categories
Find more on Digital Filtering in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!