Error using horzcat Dimensions of arrays being concatenated are not consistent. for piano note frequency analysis.

I have this error that comes up:

Error using horzcat
Dimensions of arrays being concatenated are not consistent.

Error in InputAudio (line 26)

y = [y, zeros(1, 1000000)];

The code right now takes a piano note .wav file from the directory and succesfully gives the frequency and pitch of the note. I'm now attempting to add windowing so I can separate frequencies from a simple piano song, the error is on line 26:

y = [y, zeros(1, 1000000)];

Also, if you're curious about

FrequencyToPitch(f)

this is just a range of frequencies that is related to a pitch.

This is the Code,

clear all;

%Parameters
N = 512; %Number of points in St-Ft

%User Finds Audio File 
[file,path] = uigetfile({'*.wav';},'input file');
name = fullfile(path,file);

%Playing Audio
if isequal(file,0)
   disp('User selected Cancel');
else
   disp(['User selected ', fullfile(path,file)]);
   [y, fs] = audioread(name);
    soundsc(y, fs);
end

%Fast Fourier Transform
Ns = length(y); 
t = (1/fs)*(1:Ns); 


%Zero Padding
y = y.*hanning(Ns);
y = [y, zeros(1, 1000000)];

X = fft(y);
Xk = abs(X); 
Xk = Xk(1:Ns/2); 
f = fs*(0:Ns/2-1)/Ns; 

%~~~~~~~~~~~~~~~Plots of Data~~~~~~~~~~~~~~~~%
%Plot Amp. Vs. Time(samples).
figure('color','white')
plot(t, y,'color','blue')
xlabel('Time (s)')
ylabel('Amplitude')
title('Amplittude over Time')

%FFT Plot
figure('color','white')
plot(f, Xk/max(Xk))
xlim([0 5000])
xlabel('Frequency (Hz)')
ylabel('Amplitude')
title('Fast Fourier Transform')

%Plot Mag. Vs. Bins.
figure('color','white')
plot([0:length(X)-1],abs(X))
xlabel('Bins')
ylabel('Magnitude(Freq.)')
title('Magnitude of Freq.')
%~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~%



%Find Frequency (Finds Amplitude(y) Peaks which tells Frequency(x))
x = f; % x-vector 
y = Xk/max(Xk); % y-vector 
minpeakheight = 0.2; % Minimum peak height for sampled Piano notes is around 0.2, look at FFT Plot
minpeakdistance = 1; 
[peak_vals,peak_locs] = findpeaks(y,x,'MinPeakHeight',minpeakheight,'MinPeakDistance',minpeakdistance);
r = 1; %Max and Min Peak Distances
mpd = r*0.9; 
MPD = r/0.9; 

[~,index] = max(peak_vals(peak_locs<peak_locs(1)+mpd)); % index of the frequncy peak



    
%DisplayFrequency
new_peak_locs = peak_locs(index); % position peak/Frequency Value
fprintf('The Frequency of the Note is:')
f = new_peak_locs 
new_peak_vals = peak_vals(index);

%DisplayPitch
disp('The Pitch is:')
FrequencyToPitch(f)

[Rena Berman]

(Answers Dev) Restored edit

Answer 1

[Walter Roberson]

audioread returns one column per channel. You are attempting to concatenate on a row rather than a column.

[Voltarian]

What would be a solution to this? I'm new to MatLab and this error is really confusing.

[Walter Roberson]

[y; zeros(1000000,1)]

or

[y.', zeros(1,1000000)]