MATLAB enumeration definitions can't be nested within another classdef definition, as your code attempts to do. That would be very convenient & useful, but unfortunately isn't supported currently.
You need to define your enumeration as its own class in its own @-folder. Also, note that since you've supplied your own enumeration values, your class needs to inherit support for those values. However, your numeric vector values aren't specified properly; they need to be within brackets. Here's how your classdef would need to look.. (I'm only showing the first few rows)
classdef MyColors < double
Red ([1, 0, 0])
Orange ([1,.5, 0])
Yellow ([1, 1, 0])
Unfortunately, when we try to use this, we find that vector values aren't allowed :(
In class 'MyColors', enumeration member named 'Red' must be scalar.
So you'll have to find a different way to implement your idea. I would suggest considering an ordinary classdef with constant properties, a la :
Red = [1, 0, 0];
Orange = [1,.5, 0];
Yellow = [1, 1, 0];
Now we get our desired results:
1 0 0