add zeroPole.m to ceuurent folder

main.m

@@ -22,4 +22,9 @@ plotRawSignal(X, Fs);
 % ==== Analyze frequency spectrum ====
 [f, power] = frequencySpectrum(X, Fs, 1);  % set 1 to plot
 
+% ======== Apply a bandpass filter ==============
+[filteredSignal, Z, P] = iirFilter(6, [5 20], X, 200, 1);  % Butterworth bandpass
+
+
+
 end

zeroPole.m

@@ -0,0 +1,44 @@
+function [Z,P] = zeroPole(b,a,plt)
+
+%{
+function [Z,P] = zeroPoles(b,a,plt)
+Ex: [Z,P] = zeroPoles([1 0.5 -1],[1 0 0.81],1)
+
+Task: To compute the zeros and poles of a transfer function 
+
+Inputs:
+    -a: vector of a_i (denominator)
+    -b: vector of b_i (numerator)
+    -plt: plot if greater than 0
+
+Outputs:
+    -Z: zeros (roots of the numerator)
+    -P: poles (roots of the denominator)
+
+Author: Tikea TE
+Date: 15/04/2025
+%}
+
+% ======== calculate the zeros =========
+Z = roots(b);
+% ======== calculate the poles =========
+P = roots(a);
+
+if(plt)
+    figure;
+    zplane(Z,P);
+    title("zeros and poles of H(z) in the complex plane");
+    xlabel("Real part");
+    ylabel("imaginary part");
+    legend("zeros","poles");
+    grid on;
+
+    figure;
+    impz(b,a);
+    title("Impulse response");
+    xlabel("samples (n)");
+    ylabel("amplitude of the output y")
+    grid on;
+end
+
+