title: Checking whether a matrix is SPD
body: <p>What will be the quickest (run time) way to check whether a matrix is symmetric positive definite in Matlab? I have run this test for a large number of sparse matrices whose size (dimension) varies from  10000 to 100000?</p>
  
  <p>Edit:</p>
  
  <p>Cholesky is exorbitantly costly for my purpose. I need a dirty check first if it gives an indication that matrix might be spd then I might check only those matrix more reliably using CHOL</p>