title: difference between svd() and call svd, R and IML
body: <p>I'm translating a package from R to IML, and this will be free online when it will be done :).
  I gain different results from the decomposition of a big matrix, both results seems the same when you look at them, but, if for example I take first 2 columns of U and do U'*U, my 2x2 matrix will be quite different (U_11 = 1.1e-17 and U_11 =1.4e-17). The difference is very small (3e-18) and this lead me to think that it could be something related to the number of decimals that each software use, SAS IML and R.
  Anyone knows something more about this topic? How can I test this? Thank you.</p>