From f630bce74ac65e05971fb51da144b568ae39010f Mon Sep 17 00:00:00 2001
From: sin-ha <harsh19112000@gmail.com>
Date: Wed, 1 Apr 2020 17:27:48 +0530
Subject: [PATCH] Fixed indexing

---
 interfaces/cython/cantera/composite.py        | 12 ++++++------
 interfaces/cython/cantera/test/test_thermo.py | 11 ++++++++++-
 2 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/interfaces/cython/cantera/composite.py b/interfaces/cython/cantera/composite.py
index 2c126e08a08..415254c71b2 100644
--- a/interfaces/cython/cantera/composite.py
+++ b/interfaces/cython/cantera/composite.py
@@ -523,9 +523,9 @@ def __init__(self, phase, shape=(0,), states=None, extra=None):
                         "Unable to create extra column '{}': name is already "
                         "used by SolutionArray objects.".format(name))
                 if not np.shape(v):
-                    self._extra[name] = [v]*self._shape[0]
+                    self._extra[name] = np.array([v]*self._shape[0])
                 elif len(v) == self._shape[0]:
-                    self._extra[name] = list(v)
+                    self._extra[name] = np.array(list(v))
                 else:
                     raise ValueError("Unable to map extra SolutionArray"
                                      "input for named {!r}".format(name))
@@ -536,7 +536,7 @@ def __init__(self, phase, shape=(0,), states=None, extra=None):
                     raise ValueError(
                         "Unable to create extra column '{}': name is already "
                         "used by SolutionArray objects.".format(name))
-                self._extra[name] = []
+                self._extra[name] = np.array([])
 
         elif extra:
             raise ValueError("Initial values for extra properties must be"
@@ -555,7 +555,7 @@ def __getitem__(self, index):
 
     def __getattr__(self, name):
         if name in self._extra:
-            return np.array(self._extra[name])
+            return self._extra[name]
         else:
             raise AttributeError("'{}' object has no attribute '{}'".format(
                 self.__class__.__name__, name))
@@ -590,7 +590,7 @@ def append(self, state=None, **kwargs):
             raise IndexError("Can only append to 1D SolutionArray")
 
         for name, value in self._extra.items():
-            value.append(kwargs.pop(name))
+            np.append(value,kwargs.pop(name))
 
         if state is not None:
             self._phase.state = state
@@ -628,7 +628,7 @@ def sort(self, col, reverse=False):
             indices = indices[::-1]
         self._states = [self._states[ix] for ix in indices]
         for k, v in self._extra.items():
-            self._extra[k] = list(np.array(v)[indices])
+            self._extra[k] = np.array(v)[indices]
 
     def equilibrate(self, *args, **kwargs):
         """ See `ThermoPhase.equilibrate` """
diff --git a/interfaces/cython/cantera/test/test_thermo.py b/interfaces/cython/cantera/test/test_thermo.py
index 16ba5f6b507..a5ae53f4653 100644
--- a/interfaces/cython/cantera/test/test_thermo.py
+++ b/interfaces/cython/cantera/test/test_thermo.py
@@ -1644,7 +1644,16 @@ def test_slicing_ndim(self):
     def test_extra(self):
         with self.assertRaises(ValueError):
             states = ct.SolutionArray(self.gas, extra=['creation_rates'])
-        
+
+        # test indexed operations on extra arrays 
+        states = ct.SolutionArray(self.gas, 7, extra={'n': range(7)})
+        array = np.array(range(7))
+        self.assertArrayNear(states.n , array)
+        states.n[1] = -5
+        states.n[3:5] = [0,1]
+        array_mod = np.array([ 0, -5,  2,  0,  1,  5,  6])
+        self.assertArrayNear(states.n ,array_mod)
+
     def test_append(self):
         states = ct.SolutionArray(self.gas, 5)
         states.TPX = np.linspace(500, 1000, 5), 2e5, 'H2:0.5, O2:0.4'