Error using tiledlayout syntax instead of subplot when referencing axes handles

Hello, I am trying to use the newer tiledlayout feature rather than subplots as I want to adjust the padding round each subplot. However, I have functions that require an axes handle (ax1, ax2).

Normally I do this: (and it works fine):

        ax1=subplot(4,8,[1,2,3,9,10,11],'Parent',f1);
        myImshow1(app,IM,n, ax1); %my own imshow function
        ax2=subplot(4,8,[4,5,6,7,8,13,14,15,16],'Parent',f1);
        myImshow1(app,IM2,n, ax2);

I've tried using tilelayout syntax:

t=tiledlayout(f1,2,2,'TileSpacing','Compact');
ax1=gca;
myImshow1(app,IM,n, ax1)
nexttile(t); ax2=gca;
myImshow1(app,IM2,n, ax2);

But it complains

Answer 1

[Steven Lord]

Be very careful about using gca, gcf, etc. in your code. I generally only use those when I'm experimenting in the Command Window.

Instead, call nexttile with an output argument. From its documentation page "ax = nexttile(___) returns the axes object." You can use the "Set Properties on the Axes" example on that documentation page as a model for your code, as it does something very similar to what you're trying to do.

[Jason]

OK thanks, so Im clear to positon in the 1st tile, you still have to call nextile, or would this be the 2nd tile. If so how would you gett he ax for the first tile

[dpb]

If you're only using one axes and doing different stuff to it, that'll be ok. I may have misread the original thinking trying to put two on the one tile.

What Steven L is saying is to return the axes handles when you call nexttile; you;ll need an array of graphic objects the size of the tile layout to hold them all and not destroy the previous when call nexttile the next time.

[Steven Lord]

Here's the example from the documentation page that I mentioned. I've added a few comments.

t = tiledlayout(2,1);

% First tile
ax1 = nexttile;

% You could specify ax1 as an input prior to [1 2 3 4 5] if you wanted
% to make it explicit that you were plotting into that tile.
plot([1 2 3 4 5],[11 6 10 4 18]);
ax1.XColor = [1 0 0];
ax1.YColor = 'k'; % Let's make/leave this black

% Second tile
ax2 = nexttile;
plot(ax2, [1 2 3 4 5],[5 1 12 9 2],'o'); % Here I added ax2 in the call
ax2.XColor = [0 0 1]; % Make this blue to distinguish it from ax1
ax2.YColor = [1 0 0];

Now if I wanted to, I could use ax1 or ax2 to manipulate those axes, add more stuff to those axes, etc.

text(ax1, 2.5, 12, ". This is (2.5, 12) in ax1")

If you're going to create a lot of these axes and keep their handles around, rather than using numbered variables you might want to store them in an array.

AX = gobjects(2, 1);
AX(1) = ax1;
AX(2) = ax2

AX = 
  2×1 Axes array:

  Axes
  Axes

[Jason]

Thanks for this excellent example, it clears it call up for me now.

Answer 2

[dpb]

tiledplot is only able to put one axes object per tile, sorry. Another user wanted two y-axes just yesterday...

<Answers/721489-adding-a-second-x-axis-to-each-plot-in-a-tiled-layout>

[Jason]

So how do you get the appropriate 'Parent' axis handle to be able to pass to e.g. Imshow (in appdesigner)

t=tiledlayout(f1,2,2,'TileSpacing','Compact');
imshow(myImage1,'Parent',????)
nexttile(t);
imshow(myImage2,'Parent',????)