63     double mean() const { return mean_; }  in mean()
66       return a.mean_ == b.mean_;
76     double mean_;  variable
134     : mean_(mean), split_(0) {  in param_type()
141   if (mean_ < 10) {  in param_type()
144     emu_ = std::exp(-mean_);  in param_type()
145   } else if (mean_ <= 50) {  in param_type()
147     split_ = 1 + static_cast<int>(mean_ / 10.0);  in param_type()
148     emu_ = std::exp(-mean_ / static_cast<double>(split_));  in param_type()
154     lmu_ = std::log(mean_);  in param_type()
155     double a = mean_ + 0.5;  in param_type()
157     const double mode = std::ceil(mean_) - 1;  in param_type()
208   const double a = p.mean_ + 0.5;  in operator()