Why does exportgraphics not fully work, when using yyaxis?

Why does exportgraphics not fully work, when using yyaxis?

This is my minimum working example:

clear all;clc;close all;

% create a figure composed of subplots
fig = figure('position',[100 100 600 1500],'Color',[1 1 1]);
for i = [1 3 5 7 9 11] 
    ax1 = subplot(6,2,i);
    ax2 = subplot(6,2,i+1);
    myfunction_new([ax1,ax2]);
end

% print PDF
path = ('/.../figure/');
extension = 'pdf';
baseFileName = sprintf('%s.%s','my_figure',extension);
fullFileName = fullfile(path, baseFileName); 
exportgraphics(fig,fullFileName,'ContentType','vector'); 

% function to create my graphs (within the subplots)
function myfunction_new(ax)
    if ~nargin || numel(ax) < 2
        figure()
        ax = gca();
        figure()
        ax(2) = gca();
    end
    
    % plots on the left side (i.e. on left side subplots)
    hold(ax(1),'on'); 
    yyaxis(ax(1),'right')
    plot(ax(1),1:10,rand(10,1)); 
    plot(ax(1),1:10,rand(10,1)); 
    ax(1).YAxis(1).Color = 'k';
    ax(1).YAxis(2).Color = 'b';
    hold(ax(1),'off');

    % plots on the right side (i.e. on right side subplots)
    number_groups = length(unique(rand(10,1)));
    color      = turbo(number_groups);
    markers    = repelem('o',number_groups);
    sz         = repelem(12,number_groups);
    g = gscatter(ax(2),rand(10,1),rand(10,1),rand(10,1),color,markers,sz);
    for i = 1 : number_groups
        g(i).MarkerFaceColor=g(i).Color;
    end
    axis(ax(2),'off')
    legend('off')

end

Result on monitor:

Result on PDF:

Instead, if I comment (or remove) the following commands, the PDF is generated correctly, including the plots on the right side as well:

    % yyaxis(ax(1),'right')
    plot(ax(1),1:10,rand(10,1)); 
    plot(ax(1),1:10,rand(10,1)); 
    % ax(1).YAxis(1).Color = 'k';
    % ax(1).YAxis(2).Color = 'b';

However, I would need yyaxis !

[Sim]

It might be a bug of exportgraphics, or an issue with the axes. I do not know..

Answer 1

[Voss]

Why does exportgraphics not fully work, when using yyaxis?

I don't know why, but plotyy (not recommended) seems to give the correct result in the pdf.

clear all;clc;close all;

% create a figure composed of subplots
fig = figure('position',[100 100 600 1200],'Color',[1 1 1]);
for i = [1 3 5 7 9 11] 
    ax1 = subplot(6,2,i);
    ax2 = subplot(6,2,i+1);
    myfunction_new([ax1,ax2]);
end

% print PDF
file_path = ('/.../figure/');
extension = 'pdf';
baseFileName = sprintf('%s.%s','my_figure',extension);
fullFileName = fullfile(file_path, baseFileName); 
exportgraphics(fig,fullFileName,'ContentType','vector'); 

% function to create my graphs (within the subplots)
function myfunction_new(ax)
    if ~nargin || numel(ax) < 2
        figure()
        ax = gca();
        figure()
        ax(2) = gca();
    end
    
    % plots on the left side (i.e. on left side subplots)
    hold(ax(1),'on');
%     yyaxis(ax(1),'right')
%     plot(ax(1),1:10,rand(10,1)); 
%     plot(ax(1),1:10,rand(10,1)); 
%     ax(1).YAxis(1).Color = 'k';
%     ax(1).YAxis(2).Color = 'b';
    new_ax = plotyy(ax(1),1:10,rand(10,1),1:10,rand(10,1)); %#ok<PLOTYY> 
    new_ax(1).YAxis.Color = 'k';
    new_ax(2).YAxis.Color = 'b';
    hold(ax(1),'off');

    % plots on the right side (i.e. on right side subplots)
    number_groups = length(unique(rand(10,1)));
    color      = turbo(number_groups);
    markers    = repelem('o',number_groups);
    sz         = repelem(12,number_groups);
    g = gscatter(ax(2),rand(10,1),rand(10,1),rand(10,1),color,markers,sz);
    for i = 1 : number_groups
        g(i).MarkerFaceColor=g(i).Color;
    end
    axis(ax(2),'off')
    legend('off')

end

[Sim]

thanks a lot! Yes, it works, even though I am having several troubles to convert all the pieces of codes, that were related to yyaxis, to plotyy.... Yes, I accept your nice answer, but if any workaround with yyaxis could be found, I would really appreciate it :-)