Adding Fast GSSS as an optional dependency

3rdParty/grasp_dependencies_list.m

@@ -145,4 +145,14 @@
     list(cur_dep).root_dir = 'GraphStructures-master/';
     list(cur_dep).path_list = {'ToyGraphGSPExample/'};
     list(cur_dep).optional = 1;
+
+    cur_dep = cur_dep + 1;
+
+    list(cur_dep).url = 'https://github.com/ychtanaka/FastGSSS/archive/master.zip';
+    list(cur_dep).name = 'fast_gsss/';
+    list(cur_dep).root_dir = 'FastGSSS-master/';
+    list(cur_dep).path_list = {'.'};
+    list(cur_dep).optional = 1;
+    list(cur_dep).ref_bib = 'To appear in IEEE TSP';
+    list(cur_dep).dependencies = {'sgwt'};
 end

Operators/grasp_translation.m

@@ -1,11 +1,16 @@
-%Computes the graph translation [Girault et al. 2015, IEEE SPL].
+%Computes the graph translation operator [Girault et al. 2015, IEEE SPL].
 %
-%   T = GRASP_TRANSLATION(graph) uses the graph structure to build its
-%   graph translation.
+%   filter = GRASP_TRANSLATION(graph) uses the graph structure to build its
+%       graph translation.
 %
-%   T = GRASP_TRANSLATION(..., freqs) use the given frequencies instead of
-%   the ones from [Girault et al. 2015, IEEE SPL]. The resulting operator
-%   verifies T\chi_l=exp(-i * 2 * pi * freqs(l)) \chi_l.
+%   filter = GRASP_TRANSLATION(..., freqs) use the given frequencies 
+%       instead of the ones from [Girault et al. 2015, IEEE SPL]. The 
+%       resulting operator verifies 
+%       T\chi_l=exp(-i * 2 * pi * freqs(l)) \chi_l.
+%
+%   [..., T] = GRASP_TRANSLATION(...) also returns the matrix of the graph
+%       translation operator. This may be faster than using
+%       GRASP_APPLY_FILTER.
 %
 % Authors:
 %  - Benjamin Girault <benjamin.girault@ens-lyon.fr>
@@ -48,17 +53,27 @@
 % The fact that you are presently reading this means that you have had
 % knowledge of the CeCILL license and that you accept its terms.
 
-function T = grasp_translation(graph, freqs)
+function [filter, T] = grasp_translation(graph, freqs)
+    %% Check
+    if ~isfield(graph, 'fourier_version') || strcmp(graph.fourier_version, 'n.a.')
+        error('GraSP:Translation:MissingGFT', 'Missing GFT! Please run grasp_eigendecomposition first.');
+    end
+
     %% Use the provided freqs if given
     if nargin == 2
-        T = grasp_fourier_inverse(graph, diag(exp(-1i * 2 * pi * freqs)));
+        filter.type = 'convolution';
+        filter.data = exp(-1i * 2 * pi * freqs);
+        if nargout == 2
+%             T = grasp_fourier_inverse(graph, diag(exp(-1i * 2 * pi * freqs)));
+            T = grasp_apply_filter(graph, filter);
+        end
         return;
     end
 
     %% Intialization
     if ~strcmp(graph.fourier_version, 'standard laplacian') && ~strcmp(graph.fourier_version, 'normalized laplacian')
         if ~(strcmp(graph.fourier_version, 'graph shift') && ~grasp_is_directed(graph))
-            error('Error: The Fourier transform should be the result of the decomposition of a Laplacian matrix, or a symmetric graph shift!');
+            error('GraSP:Translation:InvalidGFT', 'Error: The Fourier transform should be the result of the decomposition of a Laplacian matrix, or a symmetric graph shift!');
         end
     end
 
@@ -76,5 +91,9 @@
     end
 
     %% Translation operator
-    T = expm(-1i * pi * sqrtm(full(graph.L) / rho));
+    filter.type = 'kernel';
+    filter.data = @(x) exp(-1i * pi * sqrtm(x / rho));
+    if nargout == 2
+        T = expm(-1i * pi * sqrtm(full(graph.Z) / rho));
+    end
 end

Plotting/grasp_generate_gif.m

@@ -47,29 +47,70 @@
 % The fact that you are presently reading this means that you have had
 % knowledge of the CeCILL license and that you accept its terms.
 
-function grasp_generate_gif(fh, filename, graph, signals, titles, title_font_size, show_graph_options)
+function grasp_generate_gif(fh, filename, graph, signals, titles, title_font_size, show_graph_options, varargin)
+    %% Parameters
+    default_param = struct(...
+        'signals_delays', 0.1,...
+        'overlay_function', [],...
+        'overlay_update', []);
+    if nargin == 7
+        options = struct;
+    elseif nargin > 8
+        options = cell2struct(varargin(2:2:end), varargin(1:2:end), 2);
+    else
+        options = varargin{1};
+    end
+    options = grasp_merge_structs(default_param, options);
+
+    %% Initializations
     ah = get(fh, 'CurrentAxes');
+%     disp('<show_graph>');
     nh = grasp_show_graph(ah, graph, show_graph_options);
+%     disp('</show_graph>');
+    overlay_h = [];
+    if numel(options.overlay_function) > 0
+        hold(ah, 'on');
+        overlay_h = options.overlay_function(ah);
+        hold(ah, 'off');
+    end
     colorbar;
+%         disp('<set>');
     set(fh, 'color', 'w');
+%         disp('</set>');
+    if numel(options.signals_delays) == 1
+        options.signals_delays = options.signals_delays * ones(size(signals, 2), 1);
+    end
 
+    %% Code
+%         disp('<set>');
+    set(nh, 'CData', signals(:, 1));
+%         disp('</set>');
+    if numel(options.overlay_update) > 0
+        options.overlay_update(overlay_h, 1);
+    end
+    drawnow;
     f = getframe(fh);
     if ~grasp_is_octave()
         [im, map] = rgb2ind(f.cdata, 256, 'nodither');
     else
         [im, map] = rgb2ind(f.cdata);
     end
-    imwrite(im, map, filename, 'DelayTime', 0.1, 'LoopCount', inf);
-    for k = 1:size(signals, 2)
+    imwrite(im, map, filename, 'DelayTime', options.signals_delays(1), 'LoopCount', inf);
+    for k = 2:size(signals, 2)
         title(ah, titles{k}, 'interpreter', 'latex', 'fontsize', title_font_size);
+%         disp('<set>');
         set(nh, 'CData', signals(:, k));
+%         disp('</set>');
+        if numel(options.overlay_update) > 0
+            options.overlay_update(overlay_h, k);
+        end
         drawnow;
         f = getframe(fh);
         if ~grasp_is_octave()
             [im, map] = rgb2ind(f.cdata, 256, 'nodither');
         else
             [im, map] = rgb2ind(f.cdata);
         end
-        imwrite(im, map, filename, 'DelayTime', 0.1, 'WriteMode', 'append');
+        imwrite(im, map, filename, 'DelayTime', options.signals_delays(k), 'WriteMode', 'append');
     end
 end

RELEASENOTES.md

@@ -22,6 +22,8 @@
 
 ### New Third Party Toolboxes
 
+ * [FastGSSS](https://github.com/ychtanaka/FastGSSS)
+
 ### New Functions
 
  * `grasp_clean_pdf_export`: Function to create nice PDFs, not cropped ones...

doc/tuto.mwk

@@ -51,6 +51,6 @@ Now that the GFT is defined, we can compute a more complex signal using [[grasp_
 
 This signal is a low pass signal. We can then convolve the two signals using:
 
- conv_sig = grasp_convolution(heat, delta_1);
+ conv_sig = grasp_convolution(g, heat, delta_1);
 
 You can find more operators in the [[Operators]] folder.