ISOpureS2.model_optimize.opt_cc: Optimize the tumor-specific cancer profiles in step 2
Description
Optimize the tumor-specific cancer profiles.
Because cc is constrained (each cc_i are parameters of multinomial/discrete distribution), we
don't directly optimize the likelihood function w.r.t. cc, but we perform change of variables
to do unconstrained optimization. We therefore store these unconstrained variables in the
field "cc_weights", and update these variables.