Another tighter test

Author: pgleeson

PyNN/.test.pynn9nest.omt

@@ -14,7 +14,7 @@ experiments:
         spike detection: 
           method: threshold
           threshold: -55
-        tolerance: 0.0003082
+        tolerance: 0.00030816640986148277
   EIF_cond_exp_isfa_ista:
     observables:
       spike times:
@@ -25,7 +25,7 @@ experiments:
         spike detection: 
           method: threshold
           threshold: -45
-        tolerance: 0.0001675
+        tolerance: 0.00016744809109184723
   pop_post2:
     observables:
       spike times:
@@ -36,7 +36,7 @@ experiments:
         spike detection: 
           method: threshold
           threshold: -63.5
-        tolerance: 0.0001403
+        tolerance: 0.00014027868699162797
 
   spike_rate_IF_curr_alpha_0:
     observables: