fix: move random number generation into numba

Copy of what @amoodie did in DeltaRCM#27

pyDeltaRCM/init_tools.py

@@ -100,7 +100,7 @@ def import_files(self):
         if self.seed is not None:
             if self.verbose >= 2:
                 print("setting random seed to %s " % str(self.seed))
-            np.random.seed(self.seed)
+            shared_tools.set_random_seed(self.seed)
 
     def set_constants(self):
 

pyDeltaRCM/shared_tools.py

@@ -19,6 +19,14 @@ def get_jwalk():
                      [0, 0, 0],
                      [1, 1, 1]])
 
+@njit
+def set_random_seed(_seed):
+    np.random.seed(_seed)
+
+
+@njit
+def get_random_uniform(N):
+    return np.random.uniform(0, 1, N)
 
 @njit
 def get_flux_wt(qx, qy, ivec, jvec):

tests/test_yaml_parsing.py

@@ -6,6 +6,7 @@
 
 from pyDeltaRCM.deltaRCM_driver import pyDeltaRCM
 
+from pyDeltaRCM.shared_tools import set_random_seed, get_random_uniform
 
 # utilities for file writing
 def create_temporary_file(tmp_path, file_name):
@@ -105,13 +106,13 @@ def test_random_seed_settings_value(tmp_path):
     p, f = create_temporary_file(tmp_path, file_name)
     write_parameter_to_file(f, 'seed', 9999)
     f.close()
-    np.random.seed(9999)
-    _preval_same = np.random.uniform()
-    np.random.seed(5)
-    _preval_diff = np.random.uniform(1000)
+    set_random_seed(9999)
+    _preval_same = get_random_uniform(1)
+    set_random_seed(5)
+    _preval_diff = get_random_uniform(1000)
     delta = pyDeltaRCM(input_file=p)
     assert delta.seed == 9999
-    _postval_same = np.random.uniform()
+    _postval_same = get_random_uniform(1)
     assert _preval_same == _postval_same