# help with adding the text location

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Abdelmalek Benaimeur on 5 Jun 2019
Edited: Sven Merk on 14 Jul 2023
is possible to add a text to a figure in the northeast or northwest of th axes?
when reading the documentation i found this , text(x,y,txt)
but for some reason i don't always know what xlim and ylim are so i cannot predicte what to put in x and y
so any ideas ?

Star Strider on 5 Jun 2019
You should be able to determine what xlim and ylim are after you do the plot.
Try this:
x = -10:10;
y = (rand(1,21)-0.5)*20;
figure
plot(x, y, 'pg')
NE = [max(xlim) max(ylim)]-[diff(xlim) diff(ylim)]*0.05;
SW = [min(xlim) min(ylim)]+[diff(xlim) diff(ylim)]*0.05;
NW = [min(xlim) max(ylim)]+[diff(xlim) -diff(ylim)]*0.05;
SE = [max(xlim) min(ylim)]+[-diff(xlim) diff(ylim)]*0.05;
text(NE(1), NE(2), 'NORTHEAST!', 'VerticalAlignment','top', 'HorizontalAlignment','right')
text(SW(1), SW(2), 'SOUTHWEST!', 'VerticalAlignment','bottom', 'HorizontalAlignment','left')
text(NW(1), NW(2), 'NORTHWEST!', 'VerticalAlignment','top', 'HorizontalAlignment','left')
text(SE(1), SE(2), 'SOUTHEAST!', 'VerticalAlignment','bottom', 'HorizontalAlignment','right'
producing:
Experiment to get the result you want.

Walter Roberson on 5 Jun 2019
You have a small number of choices:
• use legend()
• just before doing the text(), fetch the axis xlim and ylim and use those. If you need the axis limits to be able to change then if it is due to the user adding additional data, then you can use a listener to detect that; if it is due to the user resizing then you can add a ResizeFcn callback
• use a second axes that shares position with the first one, and where you position the text in coordinates relative to that second axes
• lock the relative position of the axes relative to the figure, and use annotation()

Abdelmalek Benaimeur on 5 Jun 2019
well let's me explain more
I'm working on kmeans clustering method and i'm using the function proposed by mathworks
to use it the user should precise a dataset, number of clusters,method of calculation of initial centroids and distance
and extra parameters
so what i did is that i used the function gscatter so that it gave at the end an automatic legend so that the user knows each colored set refers to which cluster (please see the attached screen shot)
now i want to add a text which shows :
number of clusters,method of calculation of initial centroids and distance
and for the text i tied to use this
Line1 = sprintf('Centr-Init Method : %s', Method);
Line2 = sprintf('Metric : %s',char(Metric));
Line3 = sprintf('Clusters : %u',Number);
% Text
Text = ...
text((x,y, {Line1,Line2,Line3},...
'HorizontalAlignment', 'Left',...
'VerticalAlignment', 'Top',...
'Fontsize', 9,...
'FontAngle', 'Normal',...
'Color', 'b',...
'EdgeColor', 'b',...
'BackGroundColor', 'w');
and i dont know how to precise the values of x and y

Sven Merk on 14 Jul 2023
Edited: Sven Merk on 14 Jul 2023
Method = "plus";
Metric = "sqeuclidean";
Clusters = 2;
some_data = rand(100,2)* 20; % multiply with 20 just to show that the data values do not matter
class = kmeans(some_data, Clusters, Distance=Metric, Start=Method);
scatter(some_data(:,1), some_data(:,2), 10, class);
lbl = "\begin{tabular}{l l}" + ...
"Center-Init Method & " + Method + "\\" + ...
"Metric & " + Metric + "\\" + ...
"Clusters & " + string(Clusters) + "\\" + ...
"\end{tabular}";
text(0.05, 0.95, lbl, Units="normalized", Interpreter="latex", VerticalAlignment="top", HorizontalAlignment="left");