MATLAB: How can i plot a graph with different y values for a particular x value

x=0.2

y=3,5,7

x=0.2 ;
y=[3,5,7]
plot(x,y,'*r')

In such cases, you need to use a marker.

 >> x = 0:0.1:3;
 >> y = (x/6).^3;
 >> plot(x,y)

No loop necessary. MATLAB will plot these correctly for you:

x = [1:5];
y = [2 3 5 6 4; 4 5 6 2 10; 13 4 12 10 4];
figure
plot(x, y)
grid

Note that if ‘y’ is a ‘numel(x) x numel(x)’ square matrix, you may have to transpose it to get the correct plot.