Today I ran into some strange problem practicing using classes in MATLAB. It seems that MATLAB cannot parse parentheses around the object.
I created a custom class called vector, which has various attributes: magnitude, angle, length in the x and y directions. I overloaded the unary minus operator so that I can have
a = vector(5,50) % creates a vector with magnitude 5 and angle 50 (in degrees)
a.ang % prints the angle
b = -a
b.ang % 230 degrees
Everything is good and good, but I will say that I want to find the angle -a in one line. You expect something like
(-a).ang
but instead i get
(-a).ang
|
Error: Unexpected MATLAB operator.
I can not use
-a.ang
or because the point operator has a higher priority than minus. Any explanation on why Matlab cannot parse parentheses around an object?
EDIT: Here I created a vector class.
classdef vector
properties
mag
ang % in degrees
x
y
end
methods
function v = vector(mag,ang)
if nargin == 2
v.mag = mag;
v.ang = ang;
v.x = mag*cosd(ang);
v.y = mag*sind(ang);
end
end
function res = plus(u,v)
x = u.x + v.x;
y = u.y + v.y;
res = vector(norm([x,y]), atan2d(y,x));
end
function res = minus(u,v)
x = u.x - v.x;
y = u.y - v.y;
res = vector(norm([x,y]), atan2d(y,x));
end
function res = uminus(v)
res = vector;
res.x = -v.x;
res.y = -v.y;
res.mag = v.mag;
res.ang = mod(v.ang+180,360);
end
end
end