How can I draw a line with arrow head between 2 data points in a plot

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Hi,
If there are 2 points in XY plane [x1, y1] and [x2, y2] then how can I draw a line with an arrowhead starting from [x1, y1] and ending at [x2, y2]. Basically, I want the plot to look like this:
[x1, y1]--------->[x2, y2]
Preferably, I like the arrow-line to bend (arc) towards the second point.
AK

Accepted Answer

Star Strider
Star Strider on 29 Oct 2014
Edited: MathWorks Support Team on 17 Mar 2021
That’s easy enough with the quiver function:
p1 = [2 3]; % First Point
p2 = [9 8]; % Second Point
dp = p2-p1; % Difference
figure
quiver(p1(1),p1(2),dp(1),dp(2),0)
grid
axis([0 10 0 10])
text(p1(1),p1(2), sprintf('(%.0f,%.0f)',p1))
text(p2(1),p2(2), sprintf('(%.0f,%.0f)',p2))
The final zero in the quiver call turns off the automatic scaling.
The arc would be a bit more challenging, depending on what you intend by arc. I would just use the quiver result.
  7 Comments
Star Strider
Star Strider on 22 Nov 2022
Moved: Dyuman Joshi on 21 Dec 2023
@Steven Lord — Thank you! (I was off doing other things for a few minutes.)

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More Answers (4)

Sajeer Modavan
Sajeer Modavan on 14 Mar 2019
Edited: Sajeer Modavan on 14 Mar 2019
t = 1:0.1:10; wo = 1;
x = 2*exp(t*wo).*sin(t*wo);
plot(t,x),hold on
plot([6 6],[-1e5 1e5],'--k','Linewidth',1.4)
plot([8.7 8.7],[-1e5 1e5],'--k','Linewidth',1.4)
ylim([-0.3e5 1e4])
% One arrow from left to right with text on left side
x = [0.74 0.79]; % adjust length and location of arrow
y = [0.3 0.3]; % adjust hieght and width of arrow
annotation('textarrow',x,y,'String',' Growth ','FontSize',13,'Linewidth',2)
% Arrow with two head at both end and text between
y = [0.4 0.4];
Xadj = 1.35; % adjust location of left arrow starting point (the sum of this with 'x' should not be negative)
annotation('textarrow',x,y,'String',' Growth ','FontSize',13,'Linewidth',2)
annotation('textarrow',-x+Xadj,y,'String','','FontSize',14,'Linewidth',2)
% One arrow from left to right with text over it
x = [0.56 0.79]; % adjust length and location of arrow
y = [0.5 0.5];
annotation('textarrow',x,y,'FontSize',13,'Linewidth',2)
annotation('textbox',[.6 .3 .7 .27],'EdgeColor','none','String','Growth','FontSize',13,'Linewidth',2)
  1 Comment
Marius Hammer
Marius Hammer on 26 Apr 2019
Could you give an describtion of how the arrow coordinates are set exactly? x and y need to be between 0 and 1 within annotation, so if I want the arrow to go from e.g. (x1,y1) = (3,0.5) and (x2,y2) = (6,0.5) how is x and y adjusted for exact location?

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Image Analyst
Image Analyst on 29 Oct 2014
I use arrow3 from the File Exchange.

Vitaly Fedoseev
Vitaly Fedoseev on 26 May 2021
Edited: Vitaly Fedoseev on 26 May 2021
The following code (Matlab R2019a) draws an arrow in the plot coordinates from point P1 to point P2. Zoom in/out shifts position of the arrow:
P1=[10,-1]; %from point
P2=[70,2]; % to point
figure;
Xlim=[-1 110];
Ylim=[-2 3];
Pos = [0.10 0.55 0.85 0.4];
subplot('Position', Pos)
hold on
X_conv(1)=Pos(1)+(Pos(3))/(Xlim(2)-Xlim(1))*(P1(1)-Xlim(1));
X_conv(2)=Pos(1)+(Pos(3))/(Xlim(2)-Xlim(1))*(P2(1)-Xlim(1));
Y_conv(1)=Pos(2)+(Pos(4))/(Ylim(2)-Ylim(1))*(P1(2)-Ylim(1));
Y_conv(2)=Pos(2)+(Pos(4))/(Ylim(2)-Ylim(1))*(P2(2)-Ylim(1));
x=0:0.1:100;plot(x, sin(x));plot([-100 1000], P2(2)*[1 1]); plot(P2(1)*[1 1], [-100 100]);
plot(x, sin(x));plot([-100 1000], P1(2)*[1 1]); plot(P1(1)*[1 1], [-100 100])
xlim(Xlim)
ylim(Ylim)
annotation('arrow', X_conv, Y_conv)

Amit K
Amit K on 30 Oct 2014
Edited: Amit K on 30 Oct 2014
Thank you guys. It worked but not good enough for what I'm doing with the plots. Is it possible to draw an arc instead of a line between the two point going from the starting point to the end point. The two points are not equidistant from the centre. Appreciate for your help.
AK

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