How to get distance & angle of a point from the center of a minor axis ??

I want to calculate the distance & angle of a point like The point in the below Image : P.S the Center Point isn't (0,0)

http://i.imgur.com/oDnVYDJ.jpg

Answer 1

[Matt Tearle]

Do you have the coordinates of the point and the center (in standard Cartesian coordinates)? If so, just use norm and atan2 of the difference between the two:

p1 = rand(2,1)
p2 = rand(2,1)
d = p2 - p1
norm(d)
atan2(d(2),d(1))

EDIT TO ADD (In response to your comment): Still the same idea -- atan(delta_y,delta_x). It seems that you have data in the form of whole vectors of (x,y) points, and a single center point, in which case:

% coordinates of points
X = [1;2;3;4];
Y = [9;8;7;6];

% coordinates of center
X0 = 2;
Y0 = 2;

% take the difference
dX = X - X0;
dY = Y - Y0;
% and calculate the length
sqrt(dX.^2 + dY.^2)
% and angle
atan2(dY,dX)
% or atan2d(dY,dX) if you prefer degrees to radians

% visualize, for sanity
plot(X,Y,'o',X0,Y0,'x')

[Haytham Mohamed]

sorry bro , but i don't understand how to get the angle . let me give u some input :

X =[1;2;3;4]

Y =[9;8;7;6]

Center Is (2,2)

How to get the angle of each point from center