Add a Title for Each Group of Subplots in a Figure Window

Suppose I have 2 rows and 4 columns of subplots in a figure window. How can I add a title for the first row and another title for the second row?

The closest command I could think of is sgtitle, which adds title to subplot grid. I read its help documentation in MATLAB 2020b; however, none of the examples there explains how it is possible to answer my question.

[dpb]

So far there is no builtin function to add more than one title or sgtille to a figure...

Answer 1

[Image Analyst]

I believe you can use text(). I think it will place text on the figure if you tell it to, instead of the current axes. Try it to see.

[dpb]

Unfortunately, that isn't so, IA...at least through R2019b

>> figure
>> for i=1:8,subplot(4,2,i);end
>> hF=gcf;
>> hT=text(0.1,0.5,'Text for Title');       % puts text on last subplot on axes coordinates
>> delete(hT)
>> hT=text(hF,0.1,0.5,'Text for Title');
Error using text
Text cannot be a child of Figure. 
>> 

One has to create another axes or refer to positions outside the axes limits...

>> clear hAx;for i=1:8,hAx(i)=subplot(4,2,i);end
>> hTxt3=text(hAx(3),1.15,1.1,'TryPlaceSubplotTitle','HorizontalAlignment','center');
>> 

By brute trial and error results in

That is roughly centered and has only slight amount of occlusion by existing axes. To do right, need to shrink the axes a little as do xlabel and friends to squeeze stuff in small avaiable space.

[dpb]

ADDENDUM:

Continuing on the above idea with the additional axes; something like what the FEX submission suptitle does (I think)

T=hAx(1).Position(2)+hAx(1).Position(4);    % the top position of subplots above figure
R=hAx(2).Position(1)+hAx(2).Position(3);    % the rightmost position of subplots
B=hAx(7).Position(2);                       % bottom, left are same as LL corner positions
L=hAx(7).Position(1);
H=T-B;                                      % the needed height of a new axes to surround
W=R-L;                                      % the width needed, ditto...
hAX=axes('Position',[L B W H],'Color','none'); % create an axes on top of the subplots
hAX.Box='off'; hAX.XAxis.Visible='off'; hAX.YAxis.Visible='off'; % hide visible stuff don't want
% now can add text where want inside this axes...
hTtlAX=text(0.5,0.5,'New Title Axis Text','HorizontalAlignment','center');

gives

[Kareem Elgindy]

I deeply appreciate both of you, Image Analyst and dpb, for your time and effort in attempting to answer my question. However, I can see that none of these answers are efficient or appealing as the titles appear squeezed between rows. One needs more space to view the titles clearer and in an appropriate manner.

Hope MATLAB Team would develop a command that can make this happen in the near future.

[dpb]

..." as the titles appear squeezed between rows."

That's "exercise" for Student :) to reduce the height of the intermediary axes to provide a little extra room...it's a little more code, but it is doable.

[Image Analyst]

You have complete control over everything if you don't like the defaults. Get a handle to the axes, and then set whatever you want, like the Position property to size and locate the axes.

h1 = subplot(2, 2, 1);
h1.Units = 'normalized'
h1.Position = [0.1, 0.2, 0.4, 0.4] % or whatever.

[dpb]

And, it's not really that complicated, just takes either some trial and error (or more thinking about the geometry and the algebra to generalize than I've got the time/interest to do at the moment to write more general code).

Again from the above starting point just the following

for i=5:6,hAx(i).Position(4)=hAx(i).Position(4)*0.9);end
hTtlAX=text(0.5,0.5*0.96,'New Title Axis Text','HorizontalAlignment','center');

results in

The actual height reduction of 4% off the nominal 50% midpoint of the outside encompassing axes was trial and error. The first line just reduces the height of the two plots above which want to insert the title by 10% of their default height.

Salt to suit...