Coordinate system

Hi

How i can change coordinate origin to point just generated?

Example: X0=rand*10 y0=rand*10

Now i have random point(1) and i want to generate new point(2) from point(1), with random angle 2pi.Also i want certain distance from point(1) eg.2.5

I tried theta=rand*2*pi y= sin(theta) x= cos(theta) ??? i don't know how to get distance to point(2)

points are not coming around point(1) I think i have to change coordinate system center of point(1)?

Can anyone give advice

Answer 1

[Walter Roberson]

To change the coordinate system, you would create a hggroup object and use makehgtform . For more information, please see here

That answers what you actually asked, but I would not recommend it in your case.

Dist = 2.5;
theta = rand*2*pi;
y = y0 + Dist * sin(theta);
x = x0 + Dist * cos(theta);

Answer 2

[Andrew Newell]

If your object is to generate some random points in a circle around (x0,y0), you could do this:

radius = 2.5;
N = 5; % put the number of points you want here
theta = rand(N,1)*pi;
x = x0 + radius*cos(theta);
y = y0 + radius*sin(theta);

Answer 3

[Matthew Simoneau]

Are you asking about transforming Cartesian to polar coordinates? If so, cart2pol will do this.

>> x0=rand*10;
>> y0=rand*10;
>> [th,r] = cart2pol(x0,y0)

th =

      0.1530
r =

      6.3984

I don't understand the rest about generating a new point.