arrow.m

Draw a line with an arrowhead.

Description

ARROW (5/20/2009) Draw a line with an arrowhead.

ARROW(Start,Stop) draws a line with an arrow from Start to Stop (points should be vectors of length 2 or 3, or matrices with 2 or 3 columns), and returns the graphics handle of the arrow(s). By itself, ARROW will use the mouse to allow selection.

ARROW DEMO & ARROW DEMO2 show 3-D & 2-D demos of the capabilities of ARROW.

ARROW PROPERTIES shows the properties that can be set (length, base angle, tip angle, width, which ends have arrowheads, etc.)

Acknowledgements

This file inspired Display A Curve With Quaternions, The Carpetplot Class, Random Boolean Network Toolbox, Arrowflow, and Quiver2.M V1.2 (Nov 2009).

• MATLAB release: MATLAB 6.5 (R13)

[Jo Williams]

Very useful, thanks. The help suggests using AXIS(AXIS) to fix the limits, I think the same effect can be acheived with AXIS MANUAL, which would be clearer.
It's also not obvious that the arrow will be a patch object, so has properties like edgecolor, facecolor, rather than line properties.

[Jan Motl]

 

[Jan Valdman]

Perfect!

[Sisi Ma]

 

[Rajib Mozumder]

I wrote the following code:

figure(1)
clf
hold on;
scatter3(X,Y,Z,'ko')
Z1 = 500;
arrow([max(X) max(Y) Z1],[min(X) min(Y) Z1],15,'BaseAngle',60, 'FaceColor',[0 1 0])

I want to make outputs (which must contain the line along with arrow head) in X-Z plane; i.e. view([180 0]), not in 3D which is good for visualization only. Unfortunately, though the line is visible, the arrow head is not seen when I go into 2D view. I tried to include 'CrossDir',[0 0 1] as suggested by the author of the script, but it didn't help. Any suggestion?

[Michael Chan]

How do you turn off the arrow heads at either ends of the start and stop points?

[Matthew M.]

Very helpful and thorough! I only have a couple of minor quibbles - 1) the author didn't make it totally clear what normal MATLAB line properties you should use to change the arrow color and arrowhead color. But it's not too hard to figure out. 2) The author didn't assign message identifiers to the warnings (like for changing the axis limits). I edited the function to add message identifiers so I could turn them off - don't need my Command Window cluttered up with a lot of orange text.

[Haochen Tang]

 

[Ryan]

Does anyone know how to add an arrow to the legend? I'm using arrow.m to draw arrows which represent data on the plot and it would be helpful to have a blue arrow in the legend.

[Kent Leung]

@Matthias, I had this problem too and just stumbled on a solution. (In fact, the problem for me was that the xlabel was disappearing.) To fix this I did:

ax1=subplot(2,1,1); [...]
axes(ax1); arrow([x1 y1],[x2 y2]); arrow fixlimits;

I always do "fixlimits" just in case. The reason I tried this was because in the help file:
"You may want to execute AXIS(AXIS) before calling arrow so it doesn't change the axes on you; arrow determines the sizes of arrow components BEFORE the arrow is plotted, so if arrow changes axis limits, arrows may be malformed."

It's not obvious that this fixed the subplot resizing problem, but it worked!

[Felix]

By far the easiest way to draw arrow compared with arrow3.m and mArrow3.m.

[Jiangmin zhang]

 

[Matthias Hunstig]

Generally works fine. However, I use subplots, e. g. 3 x 2, and some of them have arrows. Now the arrows change the size of the subplot so that the subplots are no longer of equal size. Any idea how to correct that?

[ATN]

How do I make the arrows dashed, and make the color for each arrow different, corresponding to its z value?

Adding the 'Linestyle',':' for dashed line option makes the arrows look rather strange.

For the colors, I tried creating an nx3 matrix lineColors where each row is a color for the corresponding element, and added the option " 'EdgeColor',lineColors ", but got an error:

"Color value must be a 3 element numeric vector"

Any help is appreciated. Thanks.

[Yuanye Wang]

exactly what I need. thanks a lot.

[Tobias]

Regarding W & Jacopo,

setting the view before the arrow functions solves your problem e.g.:

clc; clear; close all

xvector=[1 0 0];
yvector=[0 1 0];
zvector=[0 0 1];

figure
grid on
daspect([1 1 1])
xlabel('x [mm]', 'FontWeight', 'bold')
ylabel('y [mm]', 'FontWeight', 'bold')
zlabel('z [mm]', 'FontWeight', 'bold')

%Here goes the view setting
view([1 1 1])

arrow([0 0 0],xvector, 'EdgeColor','k','FaceColor','k')
arrow([0 0 0],yvector, 'EdgeColor','b','FaceColor','b')
arrow([0 0 0],zvector, 'EdgeColor','r','FaceColor','r')

%Not here
%view([1 1 1])

Don't no why but seems to work!

BW,
Tobi

[John Colby]

Wonderful. Thank you, Erik!!!

[Kuifeng]

 

[Jacopo]

> Christopher This code, at least on >R2009a, looks very strange.
>close all; clc;
>figure(1)
>arrow([0;0;0],[1;0;0])
>arrow([0;0;0],[0;1;0])
>arrow([0;0;0],[0;0;1])
>axis([-1 1 -1 1 -1 1])
>I'm really having trouble with 3-D plots >and arrows pointing along the 3rd axis.

I got the same problem on Matlab R2010a (7.10.0)

[Will]

Using arrow with this script yields an unusually long arrow in the z direction, which is quite annoying. I wish the z arrow didn't become long.

clc; clear; close all

xvector=[1 0 0];
yvector=[0 1 0];
zvector=[0 0 1];

figure
grid on
daspect([1 1 1])
xlabel('x [mm]', 'FontWeight', 'bold')
ylabel('y [mm]', 'FontWeight', 'bold')
zlabel('z [mm]', 'FontWeight', 'bold')
arrow([0 0 0],xvector, 'EdgeColor','k','FaceColor','k')
arrow([0 0 0],yvector, 'EdgeColor','b','FaceColor','b')
arrow([0 0 0],zvector, 'EdgeColor','r','FaceColor','r')
view([1 1 1])

Help would be greatly appreciated.

[William Mische]

This is great, I messed around with the annotations for 1.5 hours before finding this. Once I found it everything was working the way I wanted it to in a couple of minutes. Great Work!

[Dmytro Lituiev]

 

[Marco idiart]

Perfect. Just what I was needing.

[Zhibo]

Very nice utility function. I just wonder if it is possible to fix the arrow head size so that it does not change with axis- zoom or resize. Thanks!

[Richard Crozier]

Really useful, thanks!

[Miguel Gil-Pugliese]

Thanks :)

[Arthur]

Very nice, thanks

[guizhi]

can this function specify the 'LineStyle', such as '-' , '--' , '-.' , and ':'?
how to do?
thank you.

[Rishabh Kasliwal]

thanks a lot. I was trying to make a arrow in a gui window. was having difficulty in correctly saving the arrow location. using your code it works perfectly :)

[CC]

Overall, the script is very useful. However, when using this arrow script, the legend is messed up. Some of the legend symbols would show as "black" squares instead of the correct symbol. When the arrow script is not used, the legend is displayed correctly.

[hajime yamada]

Could anybody please let me know the following:

1. How to change the size of the arrow?
2. Please let me know how to change the type of the arrow head.
3. If possible, please let me know how to have arrow at both the head and tail of the vector.
4. Instead of arrow, please let me know how I can have a dot at both ends of the vector?
5. How to change the line type?

Thanks.

[ben harper]

can you please include the color options that you write on these comments to the code help lines
thank you

[Jiangmin zhang]

perfect!

[Notan]

Works great, but the Arrowtips do not look perfect by default as they are the connection of two line ends and therefore not round in pdf printouts.
You can workaround this issue by drawing the arrow in the opposite direction and use parameter: 'End','start'.
But nonetheless it would be nice if they would be perfect by default ;-)

[David]

THANK YOU!!!!

[Christopher]

This code, at least on R2009a, looks very strange.
close all; clc;
figure(1)
arrow([0;0;0],[1;0;0])
arrow([0;0;0],[0;1;0])
arrow([0;0;0],[0;0;1])
axis([-1 1 -1 1 -1 1])

I'm really having trouble with 3-D plots and arrows pointing along the 3rd axis.

[Ryan Molecke]

I found this implementation to be slow and lacking. Admittedly I was drawing thousands of arrows at extremely short lengths. Here is an inline function I wrote in about 5 minutes to draw simple arrows.

function out = draw_arrow(startpoint,endpoint,headsize)
%by Ryan Molecke

v1 = headsize*(startpoint-endpoint)/2.5;

theta = 22.5*pi/180;
theta1 = -1*22.5*pi/180;
rotMatrix = [cos(theta) -sin(theta) ; sin(theta) cos(theta)];
rotMatrix1 = [cos(theta1) -sin(theta1) ; sin(theta1) cos(theta1)];

v2 = v1*rotMatrix;
v3 = v1*rotMatrix1;
x1 = endpoint;
x2 = x1 + v2;
x3 = x1 + v3;
hold on;
% below line fills the arrowhead (black)
fill([x1(1) x2(1) x3(1)],[x1(2) x2(2) x3(2)],[0 0 0]);
% below line draws line (black)
plot([startpoint(1) endpoint(1)],[startpoint(2) endpoint(2)],'linewidth',2,'color',[0 0 0]);

[Rob Campbell]

Useful in many ways but the code is very complicated and it's not clear how to attain specific effects without trawling through the function body. Why not put demo code in a separate file?

[Aamir]

 

[Aamir]

 

[Lorenzo Guerrasio]

It looks really great...I'll start use instead of quiver!

[never change]

amazing,very useful

[Gabriel Akira Schreiber]

The arrowheads look distorted. Even the arrowheads in the demo look distorted.

[Jianbo]

Excellent. One little problem is that the arrow created is a little different from the one inserted manually through the "insert" menu. For example, the position can not be adjust by mouse.

[Hiram]

to set the color of the arrow, see this example:
axis([0 3 0 3 0 3]);
grid on
h=arrow([3 3 3],[0 0 0],36,'BaseAngle',60);
set(h, 'FaceColor', 'b');
set(h, 'EdgeColor', 'r');
Awesome application!

[Ke]

very useful.

[Saeed Taherion]

 

[Leonardo Duarte]

 

[lili kalmer]

 

[Joselito Dimayuga]

the purpose of this Dir or format is for ?????

[Dmitry Vasilyev]

OMG! Just exactly what I was looking for! Excellent job, thank you Eric!

[GDR! x]

One can change the colour of an arrow by specifying 'FaceColor' and 'EdgeColor' properties, which is, unfortunately, not documented.

[Xuzhang Shen]

good

[Alex Fard]

 

[Matthijs Klomp]

Works great.

[Tuan Hoang]

sorry, how to add this graphic handle (return value) to an existing axes, figure.

[Ahmet Sacan]

Does not work when called in a deployed application (i.e., when called from the executable generated using mcc).

[Rutty Bee]

Ruins the figure when plotting 3-D arrows with z-components. In this case, the width of the arrowhead becomes so large that the plot is rendered unusable. This is the case no matter how one tries to set its size.

[Dustin Kruse]

works perfectly

[Jorge Marin]

 

[B Gurt]

Does exactly what it needs to do.

[jonny e]

Excellent and easy to use. I'd emphasize that one should call axis(axis) prior to plotting the arrow, or the axis limits will get reset which will render the arrow incorrectly. This is noted in the help, but tucked towards the bottom.

[Ramesh Rajasekaran]

 

[Vassili Pastushenko]

does not point to (1,1)

[Vassili Pastushenko]

Good job. A small remark:

arrow([0 0],[1 1],50,10,30)

does not point to (0,1).

Probably it would be reasonable to add a feature of automatical swapping baseAngle and tipAngle, if baseAngle < tipAngle.

[Arun Karthi Subramaniyan]

Great tool. Very easy to use with detailed documentation. Thanks for sharing it with us.

[J Xu]

this program is really good, easy-use. 3x Erik.

[Nithya C.R.]

The program is really great with all the aspects of plotting a directed line excellently covered.

[heath kitson]

thanks eric

[JR P]

This is great. I hate how MATLAB uses normalized figure coordinates in their annotation() call for drawing arrows. It makes no sense and someone at MathWorks got lazy, so it becomes nearly useless. This code is exactly what they should have done.. good job Erik!

[Jasper Menger]

Nicely done. A shame by the way Matlab doesn't seem to have a builtin function for drawing arrows from the command line.

[Very satisfied]

Exactly what I needed. Perfect!

[super tanne]

 

[Shane Lin]

I add the following comment at the file head. arrow(Start,Stop,'EdgeColor','b','FaceColor','b') color arrow.

[Vijaykumar Sathyamurthi]

Thanks for this excellent tool. I hope you continue writing such winderful codes!!!

[Sharoni Shafir]

Works great, thanks!

[Amit Kesar]

Very good. Thank you.

[Changshun Deng]

Good script!

[Dave Cogdell]

This code (specifincally including the documentation (which is at the same time incomplete and inadequate) is far too complex for the simple thing(s) it does. I believe the author is an engineer: he should refrain from trying to write like a computer scientist and write like an engineer.

[Janik Zikovsky]

Very good, better than annotation('arrow') because it is in axis units!

[Ian Mackenzie]

 

[Evan Westwood]

Couldn't figure out how to make the arrow line and arrow head have a specific color. Arrowheads didn't look as nice as those you might plot in drawing/presentation packages such as Powerpoint.

[Rattikan Saelim]

 

[Nathaniel de Lautour]

Superb effort. Highly configurable, easy to use and well documented to boot.

[Olivier Marsden]

Very useful!

[Eddie Fiorelli]

Excellent work, thorough documentation. Thanks!

[Mattias Forsblom]

Excellent.

[Kelvin Rocha]

Very useful. Explanations are excellent. Exactly what I was looking for.

[Gerald Dalley]

Very nice

[ke wang]

Very Useful and convenient. Easy to use!!

[Arnd-Ragnar Rhiemeier]

Excellent package. Help topics very comprehensive. Easy to use. Quickly leads to appealing graphical output. This package is exactly what I was looking for.

[Bernhard Boeck]

That's exactly what I'm looking for

[Benedikt Halldorsson]

Neat package, but (unless I'm missing something obvious) renders itself essentially USELESS.
Try setting the linestyle of the arrow line to dotted (set(h,'linestyle',':') and then try printing it out to a file (print -depsc test.eps) and view the postscript image. The line certainly is not dotted (on Matlab 6.5). Same problem with dashed and dot-dashed lines.
I'm not sure if this is an arrow.m problem, or Matlab's.

[Jakob van de Laar]

Great package, it should be incorporated in
the standard Matlab distribution

[M Bakht]

It is just great. Amazing.

[Niclas Borlin]

Great!

[Aslak Grinsted]

 

[a c]

greatest function ever!