Copy legends while superimposing two .fig files

I would like to copy the legends from the original figure f1 & f2 to the newly superimposed image.

I'm trying the below code but it does not code correctly.

GM_req =[2 8 9 19 22 32 34 38];

for i=1:length(GM_req)
% Load figure from Upper bound
    figname=strcat('.\SMRF-50y-C4-Col-PZ-Beam-stress-UB\UB_GM_',num2str(GM_req(i)),'.fig');
    f1=openfig(figname,'invisible');
    hold on
   
 % Load figure from Lower bound 
    figname=strcat('.\SMRF-50y-C4-Col-PZ-Beam-stress-LB\LB_GM_',num2str(GM_req(i)),'.fig');
    f2=openfig(figname,'invisible');
    

    figure
    ax1 = gca;
    copyobj(allchild(get(f1, 'CurrentAxes')), ax1);
    ax2 = axes('Position',get(ax1,'Position'));
    copyobj(allchild(get(f2, 'CurrentAxes')), ax2);
    set(ax2,'Color','none','XTick',[],'YTick',[]);
    
    lb_fig = findall(f2,'Type','Line');  % get current figure handle
    ub_fig = findall(f1,'Type','Line');;  % find upper bound figure handle
    lb_legend = legend(ax1, [ub_fig(1), lb_fig(1)]);
  
    close(f1)
    close(f2)
    hold off
  
end

Answer 1

[Rasmita]

Hi Devang,

It is my understanding that, you are creating a new figure from each pair of upper and lower bound figures and trying to copy the legends from the original figures to the newly created superimposed figures.

For this you need to extract the legend object from the original figures and add it to the new figure. Here is a modified version of your code that should work:

GM_req = [2 8 9 19 22 32 34 38];

for i = 1:length(GM_req)
    % Load figure from Upper bound
    figname = strcat('.\SMRF-50y-C4-Col-PZ-Beam-stress-UB\UB_GM_',num2str(GM_req(i)),'.fig');
    f1 = openfig(figname, 'invisible');
    hold on
   
    % Load figure from Lower bound 
    figname = strcat('.\SMRF-50y-C4-Col-PZ-Beam-stress-LB\LB_GM_',num2str(GM_req(i)),'.fig');
    f2 = openfig(figname, 'invisible');
    
    % Copy plot objects to new figure
    figure
    ax1 = gca;
    copyobj(allchild(get(f1, 'CurrentAxes')), ax1);
    ax2 = axes('Position', get(ax1, 'Position'));
    copyobj(allchild(get(f2, 'CurrentAxes')), ax2);
    set(ax2, 'Color', 'none', 'XTick', [], 'YTick', []);
    
    % Copy legend objects to new figure
    lb_legend = findobj(f2, 'Type', 'Legend');
    ub_legend = findobj(f1, 'Type', 'Legend');
    new_legend = copyobj([lb_legend, ub_legend], gcf);
    set(new_legend, 'Location', 'best');
    
    % Close original figures
    close(f1)
    close(f2)
    hold off
end

This code finds the legend objects in the original figures using the ‘findobj’ function, copies them to the new figure using the ‘copyobj’ function, and sets the location of the new legend to "best" using the ‘set’ function.

For more information, please refer below documentations:

https://www.mathworks.com/help/matlab/ref/findobj.html

https://www.mathworks.com/help/matlab/ref/copyobj.html

https://www.mathworks.com/help/matlab/ref/set.html

Hope this helps!

Regards,

Rasmita