%% Add Text to Three Data Points on Graph
% This example shows how to add text descriptions with arrows that point to three data points on a graph.
% Use the linspace function to create t as a vector of 50 values between 0 and 2\pi. Create y as sine values. Plot the data.

t = linspace(0,2*pi,50);
y = sin(t);
plot(t,y)

%
% Use the text function to add a text description to the graph at the point (\pi,\sin(\pi)). The first two input arguments to this function specify the text position. The third argument specifies the text. Display an arrow pointing to the left by including the TeX markup \leftarrow in the text. Use the TeX markup \pi for the Greek letter  \pi.

x1 = pi;
y1 = sin(pi);
txt1 = '\leftarrow sin(\pi) = 0';
text(x1,y1,txt1)

%
% Add text descriptions to two more data points on the graph. By default, the data point is to the left of the text. To show the data point to the right of the text, specify the HorizontalAlignment property as 'right'. Use the TeX markup \rightarrow to display an arrow pointing to the right.

x2 = 3*pi/4;
y2 = sin(3*pi/4);
txt2 = '\leftarrow sin(3\pi/4) = 0.71';
text(x2,y2,txt2)

x3 = 5*pi/4;
y3 = sin(5*pi/4);
txt3 = 'sin(5\pi/4) = -0.71 \rightarrow';
text(x3,y3,txt3,'HorizontalAlignment','right')

% Copyright 2012 The MathWorks, Inc.