Plotting CST Farfield Polar Plot to Matlab

Hello, I would like to plot 1D Farfield radition pattern in matlab from CST.I have saved the file as text from CST but while I am reading the file in matlab and trying to plotting it is showing error. I have used the following code :

% Specify the file name

filename = '2.8off.txt'; % Replace with the name of your CST text file

% Read the data from the text file

data = readmatrix(filename);

% Extract the relevant columns

theta_deg = data(:, 1) % Theta [deg.]

phi_deg = data(:, 2); % Phi [deg.]

absDir = data(:, 3); % Abs(Dir.) [dBi]

% Convert angles to radians

theta_rad = deg2rad(theta_deg);

phi_rad = deg2rad(phi_deg);

% Plot the radiation pattern

polarplot(theta_rad, absDir, 'LineWidth', 2);

title('CST Polar Data');

But After running this I am getting this error : >> RP

Index in position 2 exceeds array bounds. Index must not exceed 1.

Error in RP (line 9)

phi_deg = data(:, 2); % Phi [deg.]

Can you please let me know how to solve it. For your information first column represent Theta [deg.], second columnPhi [deg.] and third column Abs(Dir.)[dBi ] fourth column Abs(Theta)[dBi ] ,fifth column Phase(Theta)[deg.,sixth column Abs(Phi )[dBi ], seventh column Phase(Phi )[deg.] and eighth column Ax.Ratio[dB ]

[Govind KM]

I don't think your text file is being read as a matrix correctly. Can you check the dimensions of data using the size command?

size(data)