From d5e8bae784df65ec99d7659cedc2e3247f56acf6 Mon Sep 17 00:00:00 2001
From: conrad <conrad@localhost.localdomain>
Date: Tue, 5 Aug 2025 11:30:13 +1000
Subject: [PATCH] implement mat_norm_2() for fp16 via type promoted matrix

---
 include/armadillo_bits/op_norm_meat.hpp | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/include/armadillo_bits/op_norm_meat.hpp b/include/armadillo_bits/op_norm_meat.hpp
index 583e44d7..d388b529 100644
--- a/include/armadillo_bits/op_norm_meat.hpp
+++ b/include/armadillo_bits/op_norm_meat.hpp
@@ -960,9 +960,13 @@ op_norm::mat_norm_2(const Mat<eT>& X, const typename arma_fp16_real_or_cx_only<e
   arma_debug_sigprint();
   arma_ignore(junk);
   
-  arma_stop_logic_error("norm(): matrix 2-norm currently not supported for fp16; try norm2est() instead");
+  typedef typename get_pod_type<eT>::result T;
   
-  return typename get_pod_type<eT>::result(0);
+  typedef typename promote_type<eT, float>::result promoted_eT;
+  
+  const Mat<promoted_eT> XX = conv_to< Mat<promoted_eT> >::from(X);
+  
+  return T(op_norm::mat_norm_2(XX));
   }