# Hi, I want to include the correlation coefficient on each of the subplots of GPLOTMATRIX.

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Warwick on 17 Jan 2016
Commented: Geoff Hayes on 18 Jan 2016
My problem is how do I put some text on to the subplots.
This is one of my unsuccessful attempts -
X = randn(200,3);
r = corrcoef(X);
return
[H,AX,BigAx] = gplotmatrix(X,[],[],[0.5 0.5 1],[],1,'off','none');
set(AX(1,2));
plot(AX(1,2),[0],[0],'xk');
text(.1,.9,['r = ',num2str(r(1,2),2)],'units','norm');
thanks..

Geoff Hayes on 17 Jan 2016
Warwick - I don't have the Statistics and Machine Learning Toolbox (so can't validate the following), but in your code you do
[H,AX,BigAx] = gplotmatrix(X,[],[],[0.5 0.5 1],[],1,'off','none');
where AX is an array of handles to all of the axes. The subsequent line of code
set(AX(1,2));
seems incomplete. What are you trying to set for this axes? Perhaps you intend to set AX(1,2) as the current axes so that the text is written to it. Try using axes instead as
axes(AX(1,2));
% now draw and write the text
plot(AX(1,2),[0],[0],'xk');
text(.1,.9,['r = ',num2str(r(1,2),2)],'units','norm');

Warwick on 18 Jan 2016
Thanks so much, Geoff. With that suggestion I was able to get a very satisfactory result. This is the code snippet that I'm using now - in case it helps anyone else.
X = randn(100,3);
r = corrcoef(X);
[H,AX,BigAx] = gplotmatrix(X,[],[],[0.5 0.5 1],[],1,'off','none');
for row = 1:3
for col = 1:3
if row == col; continue; end
axes(AX(row,col));
hold on
text(.1,.9,['r = ',num2str(r(row,col),2)],'units','norm');
end
end
return
Geoff Hayes on 18 Jan 2016