generating Sine wave in Graph

Hi, I am trying to plot the following graph :

yi = [3.0 -2.9 4.6 -4.4 4.5]';

ti = [0 1.1 2.2 3.3 4.4]';

plot(ti,yi,'g');

I am getting graph as in figure 1. That is it is triangular wave, but I want sine wave as shown in figure 2.

Can you please help me with it?

Figure 2:

Figure 1:

Answer 1

[Mehmed Saad]

You have 5 data points and you ve to interpolate the data between them

see interp1 (focus on methods)

For plotting in blue cross

plot(ti,yi,'bx','MarkerSize',20,'LineWidth',2)

Now interpolated data and save there result in variable tq and yq

% Your interpolation code

Now plot tq and yq on same graph

hold on
plot(tq,yq,'g--','LineWidth',2)

where tq and yq are your interpolated data