[Kinetics] Add Plog::rates() for informational purposes

include/cantera/kinetics/RxnRates.h

@@ -409,6 +409,10 @@ public:
     //! has a negative pre-exponential factor.
     void validate(const std::string& equation);
 
+    //! Return the pressures and Arrhenius expressions which comprise this
+    //! reaction.
+    std::vector<std::pair<double, Arrhenius> > rates() const;
+
 protected:
     //! log(p) to (index range) in the rates_ vector
     std::map<double, std::pair<size_t, size_t> > pressures_;

src/kinetics/RxnRates.cpp

@@ -228,6 +228,22 @@ void Plog::validate(const std::string& equation)
     }
 }
 
+std::vector<std::pair<double, Arrhenius> > Plog::rates() const
+{
+    std::vector<std::pair<double, Arrhenius> > R;
+    for (std::map<double, std::pair<size_t, size_t> >::const_iterator iter = ++pressures_.begin();
+         iter != pressures_.end();
+         ++iter) {
+        for (size_t i = iter->second.first;
+             i < iter->second.second;
+             i++) {
+            R.push_back(std::make_pair(std::exp(iter->first), rates_[i]));
+        }
+    }
+    R.pop_back(); // remove the last rate (introduced for P > P_max)
+    return R;
+}
+
 ChebyshevRate::ChebyshevRate(const ReactionData& rdata)
     : nP_(rdata.chebDegreeP)
     , nT_(rdata.chebDegreeT)