latex fix for Flat and HalfFLat

missing {}

Author: Junpeng Lao

pymc3/distributions/continuous.py

@@ -201,7 +201,7 @@ def logp(self, value):
         return tt.zeros_like(value)
 
     def _repr_latex_(self, name=None, dist=None):
-        return r'${} \sim \text{Flat}()$'.format(name)
+        return r'${} \sim \text{{Flat}}()$'.format(name)
 
 
 class HalfFlat(PositiveContinuous):
@@ -218,7 +218,7 @@ def logp(self, value):
         return bound(tt.zeros_like(value), value > 0)
 
     def _repr_latex_(self, name=None, dist=None):
-        return r'${} \sim \text{{HalfFlat}()$'.format(name)
+        return r'${} \sim \text{{HalfFlat}}()$'.format(name)
 
 
 class Normal(Continuous):