From 46de13b36367e37ce2f8bec847e7357db33d7f7e Mon Sep 17 00:00:00 2001
From: conrad <conrad@localhost.localdomain>
Date: Tue, 8 Jul 2025 23:32:03 +1000
Subject: [PATCH] use std::uniform_real_distribution with promoted type

---
 include/armadillo_bits/op_chi2rnd_meat.hpp   |  1 +
 include/armadillo_bits/op_norm2est_bones.hpp | 12 ++++++----
 include/armadillo_bits/op_norm2est_meat.hpp  | 24 +++++++-------------
 include/armadillo_bits/op_norm_meat.hpp      |  6 ++---
 4 files changed, 20 insertions(+), 23 deletions(-)

diff --git a/include/armadillo_bits/op_chi2rnd_meat.hpp b/include/armadillo_bits/op_chi2rnd_meat.hpp
index a6fcec3d..cd23ca8b 100644
--- a/include/armadillo_bits/op_chi2rnd_meat.hpp
+++ b/include/armadillo_bits/op_chi2rnd_meat.hpp
@@ -56,6 +56,7 @@ op_chi2rnd::apply_noalias(Mat<typename T1::elem_type>& out, const Proxy<T1>& P)
   arma_debug_sigprint();
   
   typedef typename T1::elem_type eT;
+  
   // we can only make a generator for float/double/long double types
   typedef typename promote_type<eT, float>::result gT;
   
diff --git a/include/armadillo_bits/op_norm2est_bones.hpp b/include/armadillo_bits/op_norm2est_bones.hpp
index 7ac004bf..2c633772 100644
--- a/include/armadillo_bits/op_norm2est_bones.hpp
+++ b/include/armadillo_bits/op_norm2est_bones.hpp
@@ -24,8 +24,10 @@
 template<typename eT>
 struct norm2est_randu_filler
   {
-  std::mt19937_64                    local_engine;
-  std::uniform_real_distribution<eT> local_u_distr;
+  typedef typename promote_type<eT, float>::result eTp;
+  
+  std::mt19937_64                     local_engine;
+  std::uniform_real_distribution<eTp> local_u_distr;
   
   inline norm2est_randu_filler();
   
@@ -36,8 +38,10 @@ struct norm2est_randu_filler
 template<typename T>
 struct norm2est_randu_filler< std::complex<T> >
   {
-  std::mt19937_64                   local_engine;
-  std::uniform_real_distribution<T> local_u_distr;
+  typedef typename promote_type<T, float>::result Tp;
+  
+  std::mt19937_64                    local_engine;
+  std::uniform_real_distribution<Tp> local_u_distr;
   
   inline norm2est_randu_filler();
   
diff --git a/include/armadillo_bits/op_norm2est_meat.hpp b/include/armadillo_bits/op_norm2est_meat.hpp
index 3199f6ea..67b75142 100644
--- a/include/armadillo_bits/op_norm2est_meat.hpp
+++ b/include/armadillo_bits/op_norm2est_meat.hpp
@@ -27,11 +27,13 @@ norm2est_randu_filler<eT>::norm2est_randu_filler()
   {
   arma_debug_sigprint();
   
+  typedef typename promote_type<eT, float>::result eTp;
+  
   typedef typename std::mt19937_64::result_type local_seed_type;
   
   local_engine.seed(local_seed_type(123));
   
-  typedef typename std::uniform_real_distribution<eT>::param_type local_param_type;
+  typedef typename std::uniform_real_distribution<eTp>::param_type local_param_type;
   
   local_u_distr.param(local_param_type(-1.0, +1.0));
   }
@@ -57,11 +59,13 @@ norm2est_randu_filler< std::complex<T> >::norm2est_randu_filler()
   {
   arma_debug_sigprint();
   
+  typedef typename promote_type<T, float>::result Tp;
+  
   typedef typename std::mt19937_64::result_type local_seed_type;
   
   local_engine.seed(local_seed_type(123));
   
-  typedef typename std::uniform_real_distribution<T>::param_type local_param_type;
+  typedef typename std::uniform_real_distribution<Tp>::param_type local_param_type;
   
   local_u_distr.param(local_param_type(-1.0, +1.0));
   }
@@ -120,24 +124,12 @@ op_norm2est::norm2est
   
   if((A.n_rows == 1) || (A.n_cols == 1))  { return op_norm::vec_norm_2( Proxy< Mat<eT> >(A) ); }
   
-  // low-precision types cannot be used for norm2est_randu_filler
-  // (std::uniform_real_distribution is undefined for types not float/double/long double)
-  norm2est_randu_filler< typename promote_type<eT, float>::result > randu_filler;
+  norm2est_randu_filler<eT> randu_filler;
   
   Col<eT> x(A.n_rows, fill::none);
   Col<eT> y(A.n_cols, fill::none);
   
-  if(is_fp16<eT>::yes)
-    {
-    // randu_filler can only fill floats, so do that and then convert
-    Col<float> tmp(y.n_elem);
-    randu_filler.fill(tmp.memptr(), tmp.n_elem);
-    arrayops::convert(y.memptr(), tmp.memptr(), tmp.n_elem);
-    }
-  else
-    {
-    randu_filler.fill(y.memptr(), y.n_elem);
-    }
+  randu_filler.fill(y.memptr(), y.n_elem);
   
   T est_old = 0;
   T est_cur = 0;
diff --git a/include/armadillo_bits/op_norm_meat.hpp b/include/armadillo_bits/op_norm_meat.hpp
index d64b5942..f26cb462 100644
--- a/include/armadillo_bits/op_norm_meat.hpp
+++ b/include/armadillo_bits/op_norm_meat.hpp
@@ -956,9 +956,9 @@ typename get_pod_type<eT>::result
 op_norm::mat_norm_2(const Mat<eT>& X, typename arma_fp16_only<eT>::result* junk)
   {
   arma_debug_sigprint();
-
-  arma_stop_logic_error("norm(): matrix 2-norm currently not supported for fp16 type");
-
+  
+  arma_stop_logic_error("norm(): matrix 2-norm currently not supported for fp16; try norm2est() instead");
+  
   return typename get_pod_type<eT>::result(0);
   }