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### Highlights from Data space to figure units conversion

• ds2nfu(varargin)
DS2NFU Convert data space units into normalized figure units.
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4.3 | 24 ratings Rate this file 166 Downloads (last 30 days) File Size: 105 KB File ID: #10656 Version: 1.2

# Data space to figure units conversion

### Michelle Hirsch (view profile)

06 Apr 2006 (Updated )

A utility function to simplify use of annotation function

File Information
Description

The annotation function, which allows you to programmatically add a wide range of annotations to your figure, requires coordinates to be specified in normalized figure units. I have found that I almost always want to specify my annotations in data space (i.e., based on the values of data displayed in an axes).
This utility function converts coordinates in data space into normalized figure coordinates, for input to annotation. Some annotations require you to specify (x,y) pairs, while others require a 4 element position vector. This function supports both syntaxes.

Here's a simple example:
% Create some data
t = 0:.1:4*pi;
s = sin(t);

% Add an annotation requiring (x,y) coordinate vectors
plot(t,s);ylim([-1.2 1.2])
xa = [1.6 2]*pi; % X-Coordinates in data space
ya = [0 0]; % Y-Coordinates in data space
[xaf,yaf] = ds2nfu(xa,ya); % Convert to normalized figure units

Note: I believe annotation was introduced in MATLAB 7.

Acknowledgements
Required Products MATLAB
MATLAB release MATLAB 7.2 (R2006a)
21 Aug 2015 Daniel Burke

### Daniel Burke (view profile)

Really great 'simple' solution! Thanks very much

08 Jun 2015 Anton Daneyko

### Anton Daneyko (view profile)

06 Nov 2014 Jan Neggers

### Jan Neggers (view profile)

works well, thank you

18 Aug 2014 Chris Godau

### Chris Godau (view profile)

Very useful, thank you. I found that changing the axis (e.g. through axis equal) only after adding annotations avoids any problems with the aspect ratio.

23 Apr 2014 Natan

### Natan (view profile)

Please consider adding functionality for the case PlotBoxAspectRatio is not [1 1 1] (in case axis image for example)

Comment only
30 Mar 2014 Lenka

### Lenka (view profile)

thanks a lot

13 Mar 2014 Chani

### Chani (view profile)

13 Sep 2013 Fernando

### Fernando (view profile)

11 Jul 2013 Abraham Asfaw

### Abraham Asfaw (view profile)

Thanks for the inspiration! I've created a version of this file with support for logarithmic axes. Here's the link.

http://www.mathworks.com/matlabcentral/fileexchange/42475

12 Jun 2012 Deepika Mohankumar

### Deepika Mohankumar (view profile)

Got what I was looking for a long time.. Thanks.

07 Feb 2012 Hannes

### Hannes (view profile)

perfect tool fpr annotation, thank you!

03 Aug 2011 Michael

### Michael (view profile)

Doesn't work with "axis square".

06 Jul 2011 Nikolas

### Nikolas (view profile)

I am using Matlab R2009b and I used this function but the coordinates that gives me back are flipped. Why?

Comment only
03 Sep 2010 Yuri K

### Yuri K (view profile)

16 Aug 2010 Michel

### Michel (view profile)

To manage log scale I have added the following line after line 86:
-----Begin code--------
if strcmp(get(hAx,'Xscale'),'log')
axlim(1:2)=log10(axlim(1:2));
x=log10(x);
end

if strcmp(get(hAx,'Yscale'),'log')
axlim(3:4)=log10(axlim(3:4));
y=log10(y);
end
----End Code----

This works for coordinates but I didn't check for position vector. Other than that it works for me.

27 May 2009 Maxie

### Maxie (view profile)

Very useful!
Can add text at the tail of the arrow using 'textarrow' ?
Thanks!

20 Mar 2009 Yan Luo

### Yan Luo (view profile)

working for me. great

24 Sep 2008 Matt Brunner

Works fine for me. Thanks for sharing.

17 Mar 2008 Till Junge

Your function doesn't work with equal axes. example:
function bla()
close all
a=pi/4;
r=0:1e-2:1;
f=@(r) 1/2*a*log(1+(tan(a*r)).^2);
createfigure(r,f(r),f)

function createfigure(X1, Y1,f)
%CREATEFIGURE(X1,Y1)
% X1: vector of x data
% Y1: vector of y data

% Auto-generated by MATLAB on 17-Mar-2008 14:49:27

% Create figure
figure1 = figure('XVisual',...
'0x22 (TrueColor, depth 24, RGB mask 0xff0000 0xff00 0x00ff)');

% Create axes
axis1=axes('Parent',figure1);
box('on');
grid('on');
hold('all');
axis equal
ylim([0,.3])
xlim([0,1])

% Create plot
plot(X1,Y1);
r=.7
the=r*pi/4
[vpx,vpy]= ds2nfu(gca,[r r],[0,f(r)]);
annotation(gcf,'arrow',vpx,vpy);
[nx,ny] = ds2nfu(gca,[r r-.2*sin(the)],[f(r) f(r)+.2*cos(the)]);
annotation(gcf,'arrow',nx,ny);

19 Feb 2008 Scott McClure

This function does not deal with log axes.

25 Apr 2007 Tim Mullen
10 Jan 2007 BenoĆ®t Valley

This a nice and useful code, but it do not work if DataAspectRatioMode or PlotBoxAspectRatioMode are set to 'manual'. So it would be even nicer if this code would be improved to managed such case.

08 Dec 2006 Scott Hirsch

Lucian -

Sorry about that! I was using a syntax introduced in R13. Easy enough fix - change '&&' to '&' in line 58 (2 times). I tested in R12, and it works with this fix. This should work for slightly older versions, too. Note that the examples won't work, though, since ANNOTATION was introduced sometime after R12.

Comment only
06 Dec 2006 Lucian P

Doesn't work in R12a

06 Dec 2006 Vivek Goyal

Easy to use, and seems to work correctly. As soon as I learned of the annotation function, I realized that I needed this coordinate conversion function. Thanks.

12 Oct 2006 Axiom .

Works as advertised. A necessity if you prefer to do your annotations in code rather than editing the plot. Thanks!

05 Oct 2006 kerr hatrick.

very useful util. for purposes of automatic plot annotation. thx++ mr Hirsch.

06 Jan 2010 1.1

17 Aug 2015 1.2

Moved source to GitHub.