From b3f420bd332bce78023d637e6ffe2673f297d595 Mon Sep 17 00:00:00 2001
From: Bastian Rieck <bastian.rieck@iwr.uni-heidelberg.de>
Date: Tue, 30 Aug 2016 13:14:14 +0200
Subject: [PATCH] Added polyline PCA script

---
 pline_pca.m | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 69 insertions(+)
 create mode 100644 pline_pca.m

diff --git a/pline_pca.m b/pline_pca.m
new file mode 100644
index 0000000..46d8b73
--- /dev/null
+++ b/pline_pca.m
@@ -0,0 +1,69 @@
+function Result = pline_pca(filename)
+
+% Clear output file
+file = fopen('Holes/pca.pline', 'w');
+fclose(file);
+
+i = 0; % Label counter might be wrong
+
+file = fopen(filename, 'r');
+while(~feof(file))
+    line = fgetl(file);
+    
+    % Skip comment lines
+    if(line(1) == '#')
+        continue;
+    end
+    
+    % Parse line
+    parsed_line = sscanf(line, '%f');   % the first two column are actually 
+                                        % integers, namely the label and
+                                        % the number of vertices.
+                   
+    label_no = parsed_line(1);
+    num_vertices = parsed_line(2);
+
+    vertices_array  = parsed_line(3:3*num_vertices+2);
+    vertices_matrix = zeros(num_vertices, 3);
+    
+    vertices_matrix(:,1) = vertices_array(1:3:end);
+    vertices_matrix(:,2) = vertices_array(2:3:end);
+    vertices_matrix(:,3) = vertices_array(3:3:end);
+      
+    [coeff, score, roots] = princomp(vertices_matrix);
+    
+    basis  = coeff(:,1:2); % first two columns form the basis of
+                           % plane
+    normal = coeff(:,3);   % normal of the plane
+    
+    % Compute error
+    mean_vertices = mean(vertices_matrix, 1);
+    error = abs((vertices_matrix-repmat(mean_vertices, num_vertices, 1))*normal);
+   
+    % Simple threshold criterion
+    if(sum(error.^2) < 1e-05)
+        out = fopen('Holes/pca.pline', 'a');
+        fprintf(out, '%s\n', line);
+        fclose(out);
+    else
+        continue;
+    end
+
+    % Plot points on plane
+    projected_points = repmat(mean_vertices,num_vertices,1)+score(:,1:2)*coeff(:,1:2)';
+    figure('visible', 'off');
+    plot3(projected_points(:,1), projected_points(:,2), projected_points(:,3), 'bl');
+    %plot3(vertices_matrix(:,1), vertices_matrix(:,2), vertices_matrix(:,3), 'bl');
+    saveas(gcf, ['Holes/', num2str(label_no, '%03d'), '_', num2str(i, '%03d'), '.png'], 'png');
+    
+    out = fopen(['Holes/', num2str(label_no, '%03d'), '_', num2str(i, '%03d'), '.txt'], 'w');
+    for j = 1:num_vertices
+        fprintf(out, '%f %f %f %f %f\n', score(j,1), score(j,2),vertices_matrix(j,1), vertices_matrix(j,2), vertices_matrix(j,3));
+    end
+    fclose(out);
+    
+    i = i+1;
+end
+fclose(file);
+
+end
\ No newline at end of file