How can I add a circle to this..

I just started learning mathlab and I wanted to plot a circle on this figure.. more like a car. please how do i do it.. x=[0,0,1,2,3,4,5,5,0] y=[0,1,1,2,2,1,1,0,0]. Thank you

Answer 1

[KSSV]

Let the center of circle be (a,b) and radius be 'r'. Use parametric equations of circle.

x = a+r*cos(theta) ; y = b+r*sin(theta) ;

You have to define theta into a array.

use hold on ;

plot(x,y,'r') ;

this will plot circle on the given plot.

[peter obi]

Worked bro. Thank you

Answer 2

[Image Analyst]

See the FAQ: http://matlab.wikia.com/wiki/FAQ#How_do_I_create_a_circle.3F

Or alternatively you could use rectangle() (believe it or not, see the help), or

plot(x,y,'MarkerSize', 100).

[peter obi]

what could be the MarkerSize?

[Image Analyst]

It looks like you accepted the Answer from the FAQ. But if you just want to put a circle on a graph, you can do it much simpler with rectangle or plot. Just experiment with different MarkerSizes to get the size you want. Typically if you don't specify it, I think it's something like 8 or so. But if you want larger, use bigger numbers. I just guessed at 100 but you could try 20 or 50 or whatever. It's probably faster because you're not plotting an array of a bunch of points like if you use a parameterized circle.

[peter obi]

Thank you bro.. worked also..