MATLAB Programming

9 Classes and Objects
to the .c field of the object’s structure. The class function creates the
polynom object, which is then returned by the constructor.
An example use of the polynom constructor is the statement
p = polynom([1 0 -2 -5])
This creates a polynomial with the specified coefficients.
Converter Methods for the Polynom Class
A converter method converts an object of one class to an object of another
class. Two of the most important converter methods contained in MATLAB
classes are double and char. Conversiontodouble produces the MATLAB
traditional matrix, although this may not be appropriate for some classes.
Conversion to char is useful for producing printed output.
The Polynom to Double Converter
The double converter method for the polynom class is a very simple M-file,
@polynom/double.m, which merely retrieves the coefficient vector.
function c = double(p)
% POLYNOM/DOUBLE Convert polynom object to coefficient vector.
% c = DOUBLE(p) converts a polynomial object to the vector c
% containing the coefficients of descending powers of x.
c = p.c;
On the object p,
p = polynom([1 0 -2 -5])
the statement
double(p)
returns
ans =
1 0 -2 -5
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