CPU.py now computes the ratios
added the derived param r_0002
Cherry picked version of the devel branch (2.3.2)

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updated version number to 2.3.2
Fixed minor bugs and improved functionalities of CPU.py

Warning: this is a cherry picked version of the devel branch (see the cherry
picked commit).

* 2.3.2:
  Cherry picked version of the devel branch (2.3.2)
  added the derived param r_0002
  CPU.py now computes the ratios