Fixed bugs with changing max/min of priors within Cosmological and Interped classes

Within the Interped (core) class, it now yields an error if the maximum is increased (or minimum decreased) post-initialization. The attributes min_limit and max_limit keep track of the original boundaries of the provided arrays, such that the maximum can be decreased and then later increased back to the original value without yielding errors.

Within the Cosmological (gw) class, the distance arrays are recalculated when the boundaries are extended, so the maximum can be increased (or minimum decreased) post-initialization.

bilby/gw/prior.py

@@ -139,7 +139,10 @@ class Cosmological(Interped):
 
     @minimum.setter
     def minimum(self, minimum):
-        self._set_limit(value=minimum, limit_dict=self._minimum)
+        if (self.name in self._minimum) and (minimum < self.minimum):
+            self._set_limit(value=minimum, limit_dict=self._minimum, recalculate_array=True)
+        else:
+            self._set_limit(value=minimum, limit_dict=self._minimum)
 
     @property
     def maximum(self):
@@ -147,11 +150,14 @@ class Cosmological(Interped):
 
     @maximum.setter
     def maximum(self, maximum):
-        self._set_limit(value=maximum, limit_dict=self._maximum)
+        if (self.name in self._maximum) and (maximum > self.maximum):
+            self._set_limit(value=maximum, limit_dict=self._maximum, recalculate_array=True)
+        else:
+            self._set_limit(value=maximum, limit_dict=self._maximum, recalculate_array=False)
 
-    def _set_limit(self, value, limit_dict):
+    def _set_limit(self, value, limit_dict, recalculate_array=False):
         """
-        Set either the limits for redshift luminosity and comoving distances
+        Set either of the limits for redshift, luminosity, and comoving distances
 
         Parameters
         ----------
@@ -159,6 +165,8 @@ class Cosmological(Interped):
             Limit value in current class' parameter
         limit_dict: dict
             The limit dictionary to modify in place
+        recalculate_array: boolean
+            Determines if the distance arrays are recalculated
         """
         cosmology = get_cosmology(self.cosmology)
         limit_dict[self.name] = value
@@ -185,6 +193,13 @@ class Cosmological(Interped):
             limit_dict['luminosity_distance'] = (
                 cosmology.luminosity_distance(limit_dict['redshift']).value
             )
+        if recalculate_array:
+            if self.name == 'redshift':
+                self.xx, self.yy = self._get_redshift_arrays()
+            elif self.name == 'comoving_distance':
+                self.xx, self.yy = self._get_comoving_distance_arrays()
+            elif self.name == 'luminosity_distance':
+                self.xx, self.yy = self._get_luminosity_distance_arrays()
         try:
             self._update_instance()
         except (AttributeError, KeyError):