Applying text with variable on a plot

Hi. I drew a trend line in the plot and want to apply text

"R^2= Rsq1", where Rsq1 is a value got from calculation.

The figure attached shows the plot and text from my code (undesirable repeat of R^2=).

How can I apply test of "R^2= 99.5" when Rsq1=99.5?

p1 = polyfit(E1(:,3),E1(:,1),1);
yfit1 = polyval(p1, E1(:,3));
X1=-0.05:0.05:0.55;
Y1=p1(1)*X1+p1(2);
SStot1 = sum((E1(:,1)-E1(:,3)).^2);
SSres1 = sum((E1(:,1)-yfit1).^2);
Rsq1 = 1-SSres1/SStot1; 
hold on
plot(X1,Y1);
txt = 'R^2 =';
text(X1,Y1,txt)

Answer 1

[Ive J]

I don't have your dataset but you can follow this example:

plot(3:10, (6:13).^2, 'k.-', 'LineWidth', 1.5)

Rsq = 0.64645;
h = gca;
pos = [h.XLim(1) + 0.1*diff(h.XLim), h.YLim(2) - 0.1*diff(h.YLim)]; % top left corner
text(pos(1), pos(2), compose("R^2 = %.2f", Rsq))