src/layers/rotary.jl: Add reference to original source.

src/layers/rotary.jl

@@ -1,3 +1,22 @@
+"""
+    Rotary Position Embeddings (RoPE)
+
+This is a port of the RoPE implementation from NeuralAttentionlib.jl, which is an implementation of
+the Rotary Position Embeddings (RoPE) described in the RoFormer paper.
+
+Original sources:
+- Paper: "RoFormer: Enhanced Transformer with Rotary Position Embedding"
+  Authors: Jianlin Su, Yu Lu, Shengfeng Pan, Ahmed Murtadha, Bo Wen
+  URL: https://arxiv.org/abs/2104.09864
+  
+- Code: NeuralAttentionlib.jl
+  Author: chengchingwen
+  Repository: https://github.com/chengchingwen/NeuralAttentionlib.jl
+
+RoPE encodes absolute positional information with a rotation matrix that naturally 
+incorporates explicit relative position dependency in self-attention formulation.
+"""
+
 """
 Calculate position-dependent frequency.
 """
@@ -135,4 +154,4 @@ function ChainRulesCore.rrule(::typeof(with_rotary_position_embedding), x::Abstr
     end
 
     return y, rotary_pullback
-end
+end