# Placing annotations at specific xy coordinates

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Vance Blake on 13 Sep 2019
Answered: Olle Trollberg on 29 Aug 2023
Just wondering but I wanted to put annotations/text boxes at specific coordinates but when I read up on the page I saw that the values of x and y in the 'dim' vector must be between 0 and 1. Im just looking for a way to place 'X's at specific xy coordinates to signify that those points are no longer being considered for my calculations?? I figured annotations would be good way to accomplish that because I wanted to avoid matlab cconsidering a plotted X as an active point and therefore valid for my calculations. If you have any work arounds or suggestions Im all ears. Thanks for the help

Adam Danz on 13 Sep 2019
Edited: Adam Danz on 13 Sep 2019
Annotations are a pain to use unless the axes are normalized to 0:1. I see no reason why Matlab cannot allow users to specify the units in annotations which would make the tool a lot more useful.
"Im just looking for a way to place 'X's at specific xy coordinates to signify that those points are no longer being considered for my calculations"
That's much easier than anything annotation can do. Simply use the xy coordinates to plot "X"'s
hold on
plot(x,y,'rx')
If you wanted rectangles for whatever reason,
widthHeight = [.1,.1];
rectangle('Position', [x-widthHeight(1)/2, y-widthHeight(2)/2, widthHeight])
Adam Danz on 14 Sep 2019
Vance Blake on 16 Oct 2019
Hey Adam how are you ? Its been a while but I have some more questions that I would really like your help with when you get the chance the link to the question is below. https://www.mathworks.com/matlabcentral/answers/485730-define-an-if-statement-based-on-on-finding-duplicate-values-between-arrays-and-then-rewrite-code-to

### More Answers (3)

Olle Trollberg on 29 Aug 2023
I recently ran into this and here is a simple way to get around it using some anonymous functions to do rescaling.
Works at least in 2022b
plot(x,y) % Create whatever plot
ax = gca;
% Define helper funcitons to normalize from axis coordinates to normalized position in figure.
xnorm = @(x)((x-ax.XLim(1))./(ax.XLim(2)-ax.XLim(1))).*ax.InnerPosition(3)+ax.InnerPosition(1)
ynorm = @(y)((y-ax.YLim(1))./(ax.YLim(2)-ax.YLim(1))).*ax.InnerPosition(4)+ax.InnerPosition(2)
annotation('textarrow',xnorm(x_in_axis_coordinates),ynorm(y_in_axis_coordinates),'string','Arrow Text');

Image Analyst on 13 Sep 2019
No, not true. If you want to place annotation text onto a plot you can use text() using the x,y that's used for that plot, whatever range it might have, which can be more than 1.
Have you tried
badIndexes = .......whatever you need to do to identify "points are no longer being considered for my calculations"
hold on
plot(x(badIndexes), y(badIndexes), 'rx', 'MarkerSize', 15, 'LineWidth', 2) % Overlay big red X's

Bruno Luong on 14 Sep 2019
There are several tool on File Exchange, such as this one