MATLAB: Add annotation to a parent figure middle left

Question

I am using code below to creat a n*1 plot:

figure1 = figure('PaperSize',[8 8]);

for i=1:N

f = subplot(N,1,i);

plot(X,Y, 'Color','k');

end

I would like to add an annotation/text to the center left of the figure, vertically.

I am using the following code to do so:

xlim = get(gca,'XLim');

ylim=get(gca,'YLim');

ht = text(xlim(1)+0.95*xlim(2),0.5*ylim(1)+0.5*ylim(2),'Absorbance [a.u.]');

set(ht,'Rotation',90);

However, the gca is getting the xlim and ylim of the last subplot, not the whole figure. Any suggestion to do so?

Following is what I want to achieve.

Answer 1

The following code might help you:

close all
figure1 = figure('PaperSize',[8 8]);
N = 5;
for i=1:N
    f = subplot(N,1,i);
    plot(rand(10,1))
%     plot(X,Y, 'Color','k');
end 
ax = subplot(N,1,round(N/2))
ht = text(ax,0,mean(ax.YLim),'Absorbance [a.u.]','HorizontalAlignment','center');
set(ht,'Rotation',90);

Refer to text, HorizontalAlignment, Text Properties & Getting handle for subplot of saved figure