Merge pull request #8 from MeraX/patch-1

Compare strings using the `==` operator.

pyKriging/krige.py

@@ -366,7 +366,7 @@ def train(self, optimizer='pso'):
         rand.seed(int(time()))
 
         # If the optimizer option is PSO, run the PSO algorithm
-        if optimizer is 'pso':
+        if optimizer == 'pso':
             ea = inspyred.swarm.PSO(Random())
             ea.terminator = self.no_improvement_termination
             ea.topology = inspyred.swarm.topologies.ring_topology
@@ -383,7 +383,7 @@ def train(self, optimizer='pso'):
             final_pop.sort(reverse=True)
 
         # If not using a PSO search, run the GA
-        elif optimizer is 'ga':
+        elif optimizer == 'ga':
             ea = inspyred.ec.GA(Random())
             ea.terminator = self.no_improvement_termination
             final_pop = ea.evolve(generator=self.generate_population,
@@ -720,4 +720,4 @@ def adjrsquares(self, rsquared, obs):
     def chisquared(self, actual, observed):
         actual = np.array(actual)
         observed = np.array(observed)
-        return np.sum( np.abs( np.power( (observed-actual)  ,2)/actual ) )
+        return np.sum( np.abs( np.power( (observed-actual)  ,2)/actual ) )