I am trying to calculate the KL divergence between the two point clouds but I am getting the following error, please help.

% Read the first point cloud

pc1 = pcread('C:\Users\amitv\Downloads\fragment.ply');

% Read the second point cloud

pc2 = pcread('C:\Users\amitv\Downloads\fragment.ply');

% Downsample the first point cloud

pc1_ds = pcdownsample(pc1,'gridAverage',0.1);

% Downsample the second point cloud

pc2_ds = pcdownsample(pc2,'gridAverage',0.1);

% Show the downsampled first point cloud

figure; pcshow(pc1_ds);

title('Downsampled First Point Cloud');

% Show the downsampled second point cloud

figure; pcshow(pc2_ds);

title('Downsampled Second Point Cloud');

% reshape the location matrix into a column vector

location1 = reshape(pc1_ds.Location,[],1);

location2 = reshape(pc2_ds.Location,[],1);

% Calculate the PDF of the downsampled first point cloud using KDE

pdf1 = fitdist(location1,'kernel','Kernel','normal','Support','unbounded','Width',1,'Mu',0,'Sigma',1);

% Calculate the PDF of the downsampled second point cloud using KDE

pdf2 = fitdist(location2,'kernel','Kernel','normal','Support','unbounded','Width',1,'Mu',0,'Sigma',1);

% Show the PDF of the downsampled first point cloud

[f1,xi1] = ksdensity(location1);

figure;

plot(xi1,f1);

title('PDF of Downsampled First Point Cloud');

% Show the PDF of the downsampled second point cloud

[f2,xi2] = ksdensity(location2);

figure;

plot(xi2,f2);

title('PDF of Downsampled Second Point Cloud');

% Define the KL divergence function

function dkl = kl_divergence(p, q)

dkl = sum(p .* (log(p) - log(q)));

end

% Calculate the KL divergence between the two PDFs

kl = kl_divergence(pdf1, pdf2);

% Print the KL divergence

fprintf('KL divergence: %f\n', kl);

errror : Error: File: kld12.m Line: 49 Column: 1

Function definitions in a script must appear at the end of the file.

Move all statements after the "kl_divergence" function definition to before the first

local function definition.

Answer 1

[Ashu]

Hi Amit,

Moving this function definition to the end of the script will resolve your error.

% Define the KL divergence function
function dkl = kl_divergence(p, q)
    dkl = sum(p .* (log(p) - log(q)));
end