code: def obfn_g0var(self):
          
  
          # Use of self.block_sep0(self.AXnr) instead of self.cnst_A0(self.X)
          # reduces number of calls to self.cnst_A0
          return self.var_y0() if self.opt['gEvalY'] else \
              self.block_sep0(self.AXnr)
docs: Variable to be evaluated in computing the TV regularisation
          term, depending on the ``gEvalY`` option value.