minor performance improvements for philox

1 files changed, 6 insertions, 4 deletions

diff --git a/modules/rng_philox.py b/modules/rng_philox.py
index b5c02483..5532cf9d 100644
--- a/modules/rng_philox.py
+++ b/modules/rng_philox.py
@@ -26,7 +26,7 @@ two_pow32_inv_2pi = np.array([2.3283064e-10 * 6.2831855], dtype=np.float32)
 

 def uint32(x):

     """Converts (N,) np.uint64 array into (2, N) np.unit32 array."""

-    return np.moveaxis(x.view(np.uint32).reshape(-1, 2), 0, 1)

+    return x.view(np.uint32).reshape(-1, 2).transpose(1, 0)

 

 

 def philox4_round(counter, key):

@@ -65,8 +65,8 @@ def philox4_32(counter, key, rounds=10):
 

 def box_muller(x, y):

     """Returns just the first out of two numbers generated by Box–Muller transform algorithm."""

-    u = x.astype(np.float32) * two_pow32_inv + two_pow32_inv / 2

-    v = y.astype(np.float32) * two_pow32_inv_2pi + two_pow32_inv_2pi / 2

+    u = x * two_pow32_inv + two_pow32_inv / 2

+    v = y * two_pow32_inv_2pi + two_pow32_inv_2pi / 2

 

     s = np.sqrt(-2.0 * np.log(u))

 

@@ -93,7 +93,9 @@ class Generator:
         counter[2] = np.arange(n, dtype=np.uint32)  # up to 2^32 numbers can be generated - if you want more you'd need to spill into counter[3]

         self.offset += 1

 

-        key = uint32(np.array([[self.seed] * n], dtype=np.uint64))

+        key = np.empty(n, dtype=np.uint64)

+        key.fill(self.seed)

+        key = uint32(key)

 

         g = philox4_32(counter, key)