title: Evolving a matrix using a genetic algorithm
body: <p>I recently discovered genetic algothims and after doing a little research I can't find any example on how to evolve structures more complex than a vector or a string. 
  Let's say that I'm using a covariance matrix for a certain computation (to compute a mahalanobis distance for example) and I want to look for a better matrix to do the job and linimize a certain criteria, are there any classic examples on how to evolve the matrix and which crossover operators to use ? </p>
  
  <p>Thanks ! </p>