From 735990bb69a4f25121c8fb1df43613666d4a63e9 Mon Sep 17 00:00:00 2001
From: Ingmar Schoegl <ischoegl@lsu.edu>
Date: Sat, 17 Jul 2021 15:44:59 -0500
Subject: [PATCH] [Python] Expose rate coefficient and standard concentration
 units

---
 interfaces/cython/cantera/_cantera.pxd | 6 ++++++
 interfaces/cython/cantera/reaction.pyx | 6 ++++++
 interfaces/cython/cantera/thermo.pyx   | 6 ++++++
 3 files changed, 18 insertions(+)

diff --git a/interfaces/cython/cantera/_cantera.pxd b/interfaces/cython/cantera/_cantera.pxd
index 4e45b527195..263379e4416 100644
--- a/interfaces/cython/cantera/_cantera.pxd
+++ b/interfaces/cython/cantera/_cantera.pxd
@@ -49,6 +49,10 @@ cdef extern from "cantera/base/xml.h" namespace "Cantera":
         XML_Node* findID(string)
         int nChildren()
 
+cdef extern from "cantera/base/Units.h" namespace "Cantera":
+    cdef cppclass CxxUnits "Cantera::Units":
+        string str()
+
 cdef extern from "cantera/base/AnyMap.h" namespace "Cantera":
     cdef cppclass CxxAnyValue "Cantera::AnyValue"
 
@@ -207,6 +211,7 @@ cdef extern from "cantera/thermo/ThermoPhase.h" namespace "Cantera":
         size_t stateSize()
         void saveState(size_t, double*) except +translate_exception
         void restoreState(size_t, double*) except +translate_exception
+        CxxUnits standardConcentrationUnits() except +translate_exception
 
         # initialization
         void addUndefinedElements() except +translate_exception
@@ -415,6 +420,7 @@ cdef extern from "cantera/kinetics/Reaction.h" namespace "Cantera":
         cbool allow_nonreactant_orders
         cbool allow_negative_orders
         cbool usesLegacy()
+        CxxUnits rate_units
 
     cdef cppclass CxxElementaryReaction2 "Cantera::ElementaryReaction2" (CxxReaction):
         CxxElementaryReaction2()
diff --git a/interfaces/cython/cantera/reaction.pyx b/interfaces/cython/cantera/reaction.pyx
index cd025c8587e..00bb8f3f6de 100644
--- a/interfaces/cython/cantera/reaction.pyx
+++ b/interfaces/cython/cantera/reaction.pyx
@@ -737,6 +737,12 @@ cdef class Reaction:
         def __get__(self):
             return self.reaction.usesLegacy()
 
+    property rate_coeff_units:
+        """Get string representation of reaction rate coefficient units"""
+        def __get__(self):
+            cdef CxxUnits rate_units = self.reaction.rate_units
+            return pystr(rate_units.str())
+
 
 cdef class Arrhenius:
     r"""
diff --git a/interfaces/cython/cantera/thermo.pyx b/interfaces/cython/cantera/thermo.pyx
index 26c9a0a2bb8..a90a6cc03b9 100644
--- a/interfaces/cython/cantera/thermo.pyx
+++ b/interfaces/cython/cantera/thermo.pyx
@@ -1570,6 +1570,12 @@ cdef class ThermoPhase(_SolutionBase):
         def __set__(self, double value):
             self.thermo.setElectricPotential(value)
 
+    property standard_concentration_units:
+        """Get standard concentration units for this phase."""
+        def __get__(self):
+            cdef CxxUnits units = self.thermo.standardConcentrationUnits()
+            return pystr(units.str())
+
 
 cdef class InterfacePhase(ThermoPhase):
     """ A class representing a surface or edge phase"""