MATLAB Programming

Example — A Polynomial Class
• A polynom to char converter
• A display method
• A subsref method
• Overloaded +, -,and* operators
• Overloaded roots, polyval, plot, anddiff functions
The Polynom Constructor Method
Here is the polynom class constructor, @polynom/polynom.m.
function p = polynom(a)
%POLYNOM Polynomial class constructor.
% p = POLYNOM(v) creates a polynomial object from the vector v,
% containing the coefficients of descending powers of x.
if nargin == 0
p.c = [];
p = class(p,'polynom');
elseif isa(a,'polynom')
p = a;
else
p.c = a(:).';
p = class(p,'polynom');
end
Constructor Calling Syntax
You can call the polynom constructor method with one of three different
arguments:
• No input argument — If you call the constructor function with no
arguments, it returns a polynom object with empty fields.
• Input argument is an object — If you call the constructor function with
an input argument that is already a polynom object, MATLAB returns
the input argument. The isa function (pronounced “is a”) checks for this
situation.
• Input argument is a coefficient vector — If the input argument is a variable
thatisnotapolynomobject,reshapeittobearowvectorandassignit
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