Communications Toolbox

Testing for Nonzero Values

To test for nonzero values in a Galois vector, or in the columns of a Galois array that has more than one row, use the any or all function. These two functions behave just like the ordinary MATLAB functions any and all, except that they consider only the underlying array elements while ignoring information about which Galois field the elements are in. Examples are below.

m = 3; randels = gf(randint(6,1,2^m),m);
if all(randels) % If all elements are invertible
    invels = randels .\ 1; % Compute inverses of elements.
else
    disp('At least one element was not invertible.');
end
alph = gf(2,4);
poly = 1 + alph + alph^3;
if any(poly) % If poly contains a nonzero value
    disp('alph is not a root of 1 + D + D^3.');
end
code = rsenc(gf([0:4;3:7],3),7,5); % Each row is a codeword.
if all(code,2) % Is each row entirely nonzero?
    disp('Both codewords are entirely nonzero.');
else
    disp('At least one codeword contains a zero.');
end

Testing for Equality

Matrix Manipulation in Galois Fields

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