Hi guys, my code doesn't run i couldn't debug this, could you anyone help me?

% Constants and parameters
alpha = 2;  % Shear wave velocity
beta = 1;  % Compressional wave velocity
frequencies = 0:15;  % Range of frequencies
epsilon = 1e-10;  % Small epsilon value
ro = 1;  % Define the value of ro

% Define the source and receiver locations
source = [0, 0, 0];  % Source location (x, y, z)
stations = [0.01, 0, 0; 0.02, 0, 0; 0.03, 0, 0; 0.04, 0, 0; 0.05, 0, 0];  % Receiver locations (x, y, z)

% Calculate -Im G11 for different frequencies and stations
results = zeros(size(stations, 1), length(frequencies));
for i = 1:size(stations, 1)
    receiver = stations(i, :);  % Receiver location (x, y, z)
    distance = norm(receiver - source);  % Euclidean distance between source and receiver
    gamma = (receiver - source) / distance;  % Unit vector from source to receiver
    gamma = repmat(gamma, length(frequencies), 1);  % Repeat gamma for each frequency

    for j = 1:length(frequencies)
        omega = 2 * pi * frequencies(j);
        q = omega / alpha;

        f1 = (beta^2 / alpha^2) * (1 - 1j * 2 ./ (q * distance + epsilon) - 2 ./ (q^2 * distance^2 + epsilon)) * exp(-1j * q * distance);
        f2 = (beta^2 / alpha^2) * (1j ./ (q * distance + epsilon) + 1 ./ (q^2 * distance^2 + epsilon)) * exp(-1j * q * distance);

        results(i, j) = calculate_G11_imag([f1, f2], gamma(j, :), omega, ro, alpha, beta);
    end
end

ans = 1×2

1 2

ans = 1×2

1 3

Arrays have incompatible sizes for this operation.

Error in solution>calculate_G11_imag (line 48)
result = -omega / (12 * pi * ro) * (1 / (alpha^3) + 2 / (beta^3)) * sum(f .* gamma);

% Plotting
figure;
for i = 1:size(stations, 1)
    plot(frequencies, -imag(results(i, :)), 'DisplayName', sprintf('Station: %s', mat2str(stations(i, :))));
    hold on;
end
hold off;
xlabel('Frequency');
ylabel('-Im G11');
title('Variation of -Im G11 for Different Stations');
legend('Location', 'northeast');
grid on;
ylim([-1, 10]);
% Define the function to calculate -Im G11
function result = calculate_G11_imag(f, gamma, omega, ro, alpha, beta)
size(f)
size(gamma)
    result = -omega / (12 * pi * ro) * (1 / (alpha^3) + 2 / (beta^3)) * sum(f .* gamma);
end

Answer 1

[Image Analyst]

Put the fuunction definition at the END of your script, not near the beginning. Then you need to CALL IT, passing it all the arguments it needs.

Here is the debugging help you asked for:

Debugging in MATLAB | Doug's MATLAB Video Tutorials

Answer 2

[Torsten]

When you call "calculate_G11_imag", "f "has size 1x2 and "gamma" has size 1x3. Thus f .* gamma is not defined and sum(f .* gamma) cannot be evaluated.

See above for details.