Matlab 2012a drawing line segment with arrow

Matlab 2012a Self contained line Function can draw line segments , But the arrow cannot be drawn .

There is also a function called annotation, You can draw arrow segments , But unfortunately , Only in 0 To 1 Draw within the scope of , And may be out of some special consideration .

therefore , You need self-made functions to draw line segments with arrows . I found a code on the Internet , But in Matlab 2012a There are problems running in the environment , So some changes have been made . It's ready to run .

First, let's look at the effect ：

The effect is quite satisfactory , You can draw beautiful arrow segments , And the scope is not limited to 0 To 1 Within the scope of , Of course , Operational efficiency and other aspects can still be improved .

Let's go straight to the code ”

clc;clear;
x1 = [1 2];
y1 = [5 7];
h1 = drawarrow(x1,y1);
hold on;
axis([0 5 0 7]);

x2 = [3 1];
y2 = [3 5];
h2 = drawarrow(x2,y2);

  This is the test program , Here are the functions

function h = drawarrow(x,y,lineType,ax)
% https://blog.csdn.net/qq_41093957/article/details/115256114

%  The biggest problem with this program is   Changed the plot The scope of the   So that the position of the line segment is wrong 
switch nargin
    case 2
        lineType='arrow';
        ax=gca;
    case 3
        ax=gca;
end
%  Resize coordinates to fit arrow length 
% xlimraw=get(ax,'XLim');
% ylimraw=get(ax,'YLim');
xlim=get(ax,'XLim');
ylim=get(ax,'YLim');
xlimmin=xlim(1);xlimmax=xlim(2);
ylimmin=ylim(1);ylimmax=ylim(2);
if xlimmin>min(x(1),y(1)), xlimmin=min(x(1),y(1));end
if xlimmax<max(x(1),y(1)), xlimmax=max(x(1),y(1));end
if ylimmin>min(x(2),y(2)), ylimmin=min(x(2),y(2));end
if ylimmax<max(x(2),y(2)), ylimmax=max(x(2),y(2));end
% ax.XLim = [xlimmin,xlimmax];
% ax.YLim = [ylimmin,ylimmax];
set(ax,'XLim',[xlimmin,xlimmax]);
set(ax,'YLim',[ylimmin,ylimmax]);
xlim=get(ax,'XLim');
ylim=get(ax,'YLim');
% xlim=ax.XLim;
% ylim=ax.YLim;
pos=get(ax,'Position');
x_ratio = pos(3)/(xlim(2)-xlim(1));
y_ratio = pos(4)/(ylim(2)-ylim(1)); %  Zoom ratio 
orig_pos=[-xlim(1)*x_ratio+pos(1),-ylim(1)*y_ratio+pos(2)]; % figure The coordinates of the origin in the coordinate system 
x=x.*[x_ratio,y_ratio];y=y.*[x_ratio,y_ratio];
x=x+orig_pos;y=y+orig_pos;
h = annotation(lineType,[x(1),y(1)],[x(2),y(2)]);
% set(ax,'XLim',xlimraw);
% set(ax,'YLim',ylimraw);
end

Here I would like to thank the original author . There is no problem with his procedure , Just maybe not 2012a Environment , After the change , You can use it .