sinusoidal positional encoding implemented as util for embedded layer…

… in the future

src/math/positional_encoding.rs

@@ -0,0 +1,9 @@
+pub fn sinusoidal_pos_encoding(pos: usize, index: usize, embedding: usize) -> f32 {
+    let divisor = 10000f32.powf(2.0 * (index / embedding) as f32);
+
+    if index % 2 == 0 {
+        (pos as f32 / divisor).sin()
+    } else {
+        (pos as f32 / divisor).cos()
+    }
+}