From 21f23b30584bbbc58ed491a67d472ff9a0600bbe Mon Sep 17 00:00:00 2001
From: Zhengshou Lai <lai.zhengshou@outlook.com>
Date: Sun, 11 May 2025 22:45:33 +0800
Subject: [PATCH] fix

---
 src/mlpack/methods/ann/ffn_impl.hpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/mlpack/methods/ann/ffn_impl.hpp b/src/mlpack/methods/ann/ffn_impl.hpp
index 10c5c215a8..551206051a 100644
--- a/src/mlpack/methods/ann/ffn_impl.hpp
+++ b/src/mlpack/methods/ann/ffn_impl.hpp
@@ -232,7 +232,7 @@ void FFN<
   }
   
   // Perform the backward pass.
-  networkDelta.set_size(predictors.n_rows, batchSize);
+  networkDelta.set_size(predictors.n_rows, 1);
   network.Backward(networkOutput, error, gradients, networkDelta);
 }