Random ordering of figure numbers

When I installed R2015a, figure numbers were then generated in random order. I have a script that produces many graphs at once, then tiles them. I was astonished to find they would no longer display in the order executed. The figure numbers were correct but they did not arrange in numerical order when tiled. This never happened before. Any clues as to what's going on? Could it be the tiling function? I checked get(0, 'Children') and it lists the figures in reverse display order (first is last in the list). FWIW, when the tiling function is not used, figures stack on one another in numerical order.

[Jon]

Why not post the tiling function, or at least the relevant portions? I'm sure you know you can force the figure number to be whatever you'd like. If you do this, do the figures still display randomly?

[Walter Roberson]

Are you referring to the tiling feature described over here ?

[Mike Garrity]

This is just a guess, but I suspect that the code you're using to do the tiling is using GCF. If you create a bunch of figures in a row without calling drawnow, then which one becomes GCF is up to the operating system. This was always a bit unpredictable, but with the new multithreaded graphics system which was introduced in R2014b it became rather more unpredictable.

For this sort of thing, it is probably better not to depend on the value of GCF. Instead, use the return value of the figure function. Or, as you've noticed, you can look at the children of the root object. Either of those should be more predictable.

Alternatively, you could try adding some calls to drawnow to your code to try and keep the threads more in synch, but I don't think that would be a very robust solution.

But, as I said, this is just a guess and I may be all wet.

Answer 1

[Christopher Ison]

In response to the request to post the code, here it is. I think we DL'd via The Mathworks long ago. I'm interested to learn how to bring it up to date. I'm surprised this isn't included in MATLAB's core functions.

function tilefigs(tile,border)
% <cpp> tile figure windows usage: tilefigs ([nrows ncols],border_in pixels)
% Restriction: maximum of 100 figure windows
% Without arguments, tilefigs will determine the closest N x N grid

%Charles Plum                    Nichols Research Corp.
%<[e-mail]>             70 Westview Street
%Tel: [phone]             Kilnbrook IV
%Fax: [phone]             Lexington, MA 02173

maxpos  = get (0,'screensize'); % determine terminal size in pixels

maxpos(4) = maxpos(4) - 25;
hands   = get (0,'Children');   % locate fall open figure handles
hands   = sort(hands);          % sort figure handles
numfigs = size(hands,1);        % number of open figures

maxfigs = 100;

if (numfigs>maxfigs)            % figure limit check
        disp([' More than ' num2str(maxfigs) ' figures ... get serious pal'])
        return
end

if nargin == 0
  maxfactor = sqrt(maxfigs);       % max number of figures per row or column
  sq = [2:maxfactor].^2;           % vector of integer squares
  sq = sq(find(sq>=numfigs));      % determine square grid size
  gridsize = sq(1);                % best grid size
  nrows = sqrt(gridsize);          % figure size screen scale factor
  ncols = nrows;                   % figure size screen scale factor
elseif nargin > 0 
  nrows = tile(1);
  ncols = tile(2);
  if numfigs > nrows*ncols
    disp ([' requested tile size too small for ' ...
        num2str(numfigs) ' open figures '])
        return
  end
end

if nargin < 2
  border = 0;
else
  maxpos(3) = maxpos(3) - 2*border;
  maxpos(4) = maxpos(4) - 2*border;
end

xlen = fix(maxpos(3)/ncols) - 30+20; % new tiled figure width
ylen = fix(maxpos(4)/nrows) - 45-30; % new tiled figure height

% tile figures by postiion 
% Location (1,1) is at bottom left corner

pnum=0;

for iy = 1:nrows
  ypos = maxpos(4) - fix((iy)*maxpos(4)/nrows) + border +25; % figure location (row)
  for ix = 1:ncols
        xpos = fix((ix-1)*maxpos(3)/ncols + 1) + border+7;     % figure location (column)
        pnum = pnum+1;
    if (pnum>numfigs)
                break
    else
          figure(hands(pnum))
      set(hands(pnum),'Position',[ xpos ypos xlen ylen ]); % move figure
    end
  end
end

return

[Jon]

How are you creating the figures? In a loop like this?

for i = 1:N
   figure(i) = plot(whatever);
end