Add new functions

Functions/EQ_visuals/showEQNoisePSD.m

@@ -0,0 +1,44 @@
+function showEQNoisePSD(eq_noise, options)
+arguments
+    eq_noise 
+    options.postfilter_taps = NaN
+    options.fignum (1,1) double = NaN % Default to NaN if not provided
+    options.displayname (1,:) char = '' % Default to an empty string if not provided
+    options.color = [0.2157    0.4941    0.7216];
+end
+
+    % Determine the figure number to use or create a new figure
+    if isnan(options.fignum)
+        fig = figure; % Create a new figure and get its handle
+    else
+        fig = figure(options.fignum); % Use the specified figure number
+    end
+    hold on
+    ax = gca;
+    % N = numel(ax.Children);
+    N = sum(arrayfun(@(x) strcmp(x.LineStyle, '-'), ax.Children));
+    cmap = linspecer(8);
+    options.color = cmap(mod(N, size(cmap, 1)) + 1, :);
+
+    % Ensure the figure is ready before calling spectrum
+    eq_noise.spectrum("displayname", options.displayname, "fignum", fig.Number, "normalizeTo0dB", 1,"color",options.color);
+    title('Noise of soft decision signal (not MLSE)')
+
+    if ~isnan(options.postfilter_taps)
+        % Hold on to the figure for further plotting
+        hold on;
+    
+        % Compute the frequency response of the postfilter
+        [h, w] = freqz(1, options.postfilter_taps, length(eq_noise), "whole", eq_noise.fs);
+        h = h / max(abs(h)); % Normalize the filter response
+    
+        % Adjust frequency axis to center at 0
+        w_ = (w - eq_noise.fs / 2);
+    
+        % Plot the inverted postfilter response
+        plot(w_ * 1e-9, 20 * log10(fftshift(abs(h))), 'DisplayName', ['Burg Coeffs: ', num2str(round(options.postfilter_taps, 2)), ' '], 'LineWidth', 1,'Color',options.color,'LineStyle','--');
+    
+        % Ensure a legend is displayed
+        legend('show');
+    end
+end