fix pca transform loading

Author: jamesamcl

ols_embed/server.py

@@ -140,8 +140,10 @@ def embed():
 
         # Apply PCA transformation if needed
         if use_pca and pca_transformer is not None:
-            # PCA transformer expects the data in the same format it was trained on
-            embeddings_array = pca_transformer.transform(embeddings_array.astype(np.float64))
+            # PCA transformer is a dict with 'mean_' and 'components_'
+            # Transform: (X - mean) @ components
+            embeddings_array = embeddings_array.astype(np.float64)
+            embeddings_array = (embeddings_array - pca_transformer['mean_']) @ pca_transformer['components_']
             embeddings_array = embeddings_array.astype(np.float32)
 
         num_vectors, dimension = embeddings_array.shape