Improve comment about magic seeding constants

Author: bmerry

src/katgpucbf/fgpu/engine.py

@@ -501,8 +501,9 @@ def __init__(self, output: Output, engine: "Engine", context: AbstractContext, d
             engine.n_samples,
             self.spectra,
             output.spectra_per_heap,
-            # Magic constant is random, and just to ensure the seed isn't the same
-            # as other engines that also use the sync_time for seeding
+            # The magic constant was chosen at random. It ensures that the
+            # seed won't be the same as in other types of engine that also use
+            # sync_time as the basis for seeding.
             seed=int(engine.time_converter.sync_time) ^ 0x9CC11336C8B170B7,
             sequence_first=engine.feng_id,
             sequence_step=engine.n_ants,

src/katgpucbf/xbgpu/engine.py

@@ -362,8 +362,9 @@ def __init__(
             n_batches=engine.heaps_per_fengine_per_chunk,
             n_ants=engine.n_ants,
             n_channels_per_substream=engine.n_channels_per_substream,
-            # Magic constant is random, and just to ensure the seed isn't the same
-            # as other engines that also use the sync_time for seeding
+            # The magic constant was chosen at random. It ensures that the
+            # seed won't be the same as in other types of engine that also use
+            # sync_time as the basis for seeding.
             seed=int(engine.time_converter.sync_time) ^ 0xFA9D9B2093B458D5,
             sequence_first=engine.channel_offset_value,
             sequence_step=engine.n_channels,