projectData.m

function Z = projectData(X, U, K)
  %PROJECTDATA Computes the reduced data representation when projecting only 
  %on to the top k eigenvectors
  %   Z = projectData(X, U, K) computes the projection of 
  %   the normalized inputs X into the reduced dimensional space spanned by
  %   the first K columns of U. It returns the projected examples in Z.

  uReduce = U(:, 1:K);
  Z = X * uReduce;
end