How to insert arrows at the middle of each of the parallel lines

In the follwoing I want to insert arrows at the middle of each of the parallel lines

p = 0.01:.05:1;
figure(1)
plot([0; 1],[p; p], 'color','b');
x = [0.3,0.5];
y = [p,p+0.1];
a = annotation('arrow',x,y);

How to do that ? But my code does not work

[KSSV]

Can you show a pictorial example of what you expect?

[Atom]

[Atom]

The example is like this. I have to draw parallel lines to x-axis and insert arrows like the fig in the middle of the each line.

Answer 1

[KSSV]

Why annotation for this? You can use quiver. Play around with the below code.

clc; clear all ;
p = 0.01:.05:1;

x =[0;1] ; 
y = [p ;p] ; 



x1 = repmat(0.5,1,20);
y1 = p ; 
u1 = -0.2*ones(size(y1)) ;
v1 = zeros(size(x1)) ;


figure(1)
hold on
plot(x,y, 'color','b');
quiver(x1,p,u1,v1)
quiver(x1+0.1,p,u1,v1)

[Atom]

Thank you. I would like to change the arrow shape as per the fig I have attached before. Possible?

[KSSV]

That would be tough using quiver...but you can try changing the width of the arrow, read the documentation.

[Atom]

ok

Answer 2

[Mehmed Saad]

https://www.mathworks.com/matlabcentral/answers/92988-how-do-i-plot-a-line-that-has-an-arrow-on-the-end-of-it-in-2-d-and-3-d

https://www.mathworks.com/matlabcentral/fileexchange/278-arrow

[Atom]

Thank you but it is not what I need. I have to draw parallel lines to x-axis and insert arrows like the fig in the middle of the each line as shown in the fig above.

[Mehmed Saad]

use FEX file arrow. It is easy to use.