How can I change a certain part of a graph to a certain constant value?

For example, this is a sine graph.

x = linspace(0,2*pi,100);

y = sin(x);

plot(x,y)

How to change the value of y to be y = sin(0.2*pi) at x = 0.2*pi to 0.8*pi? so that the graph appears to be sine graph, except it is a horizontal straight line from x = 0.2*pi to 0.8*pi.

Thank you in advance.

Answer 1

[Andrew Newell]

Here is one way:

y(x>=0.2*pi & x<=0.8*pi) = sin(0.2*pi);

Note that I use inequalities because there are no values of x that are exactly 0.2*pi or 0.8*pi.