function polyK = polyKernel(X1, X2, kernelParams)
%Compute the poly kernel on some data. 
%
degree = kernelParams.degree;

if isfield(kernelParams, 'b') 
    b = kernelParams.b;
else 
    b = 1;
end 

numX1Examples = size(X1, 1); 
numX2Examples = size(X2, 1);
numFeatures = size(X1, 2);

polyK = (X1*X2' + b).^degree;