Varying channel coding in LTEDownlinkSim.m (MATLAB 2013a)

How can I change the channel coding schemes from the mother coding rate of 1/3 to 1/2, 2/3 and 4/5. I am using LTEDownlinkSim.m in MATLAB 2-13a. I tried but seems there are too much inter dependencies. Any pointers where shall I restart with !

In literature it is mentioned that with the help of rate Matching (RM) module following the Turbo encoder, it possible to get other code rates, if desired. Increasing and decreasing the code rate is done via puncturing and repetition, respectively. Both, puncturing and repetition are integrated in the Rate Matching module.

Any pointer on how to perform the same.