From 21a40622a0f542a7cf6ae695f2230205ecc3f445 Mon Sep 17 00:00:00 2001
From: Jaron Kent-Dobias <jaron@kent-dobias.com>
Date: Tue, 5 Jan 2021 12:02:45 +0100
Subject: Eliminated one pesky helper function.

---
 tensor.hpp | 17 ++++++-----------
 1 file changed, 6 insertions(+), 11 deletions(-)

(limited to 'tensor.hpp')

diff --git a/tensor.hpp b/tensor.hpp
index 9e860d9..a2170a8 100644
--- a/tensor.hpp
+++ b/tensor.hpp
@@ -7,12 +7,6 @@
 
 #include "factorial.hpp"
 
-template <class Scalar, unsigned p, std::size_t... Indices>
-void setJ(Scalar z, Eigen::Tensor<Scalar, p>& J, const std::array<unsigned, p>& is,
-          std::index_sequence<Indices...>) {
-  J(std::get<Indices>(is)...) = z;
-}
-
 template <class Scalar, unsigned p, std::size_t... Indices>
 Eigen::Tensor<Scalar, p> initializeJ(unsigned N, std::index_sequence<Indices...>) {
   std::array<unsigned, p> Ns;
@@ -20,13 +14,14 @@ Eigen::Tensor<Scalar, p> initializeJ(unsigned N, std::index_sequence<Indices...>
   return Eigen::Tensor<Scalar, p>(std::get<Indices>(Ns)...);
 }
 
-template <class Scalar, unsigned p, class Distribution, class Generator>
+template <class Scalar, unsigned p, class Distribution, class Generator, std::size_t... Indices>
 void populateCouplings(Eigen::Tensor<Scalar, p>& J, unsigned N, unsigned l,
-                       std::array<unsigned, p> is, Distribution d, Generator& r) {
+                       std::array<unsigned, p> is, Distribution d, Generator& r,
+                       std::index_sequence<Indices...> ii) {
   if (l == 0) {
     Scalar z = d(r);
     do {
-      setJ<Scalar, p>(z, J, is, std::make_index_sequence<p>());
+      J(std::get<Indices>(is)...) = z;
     } while (std::next_permutation(is.begin(), is.end()));
   } else {
     unsigned iMin;
@@ -38,7 +33,7 @@ void populateCouplings(Eigen::Tensor<Scalar, p>& J, unsigned N, unsigned l,
     for (unsigned i = iMin; i < N; i++) {
       std::array<unsigned, p> js = is;
       js[p - l] = i;
-      populateCouplings<Scalar, p, Distribution, Generator>(J, N, l - 1, js, d, r);
+      populateCouplings<Scalar, p>(J, N, l - 1, js, d, r, ii);
     }
   }
 }
@@ -48,7 +43,7 @@ Eigen::Tensor<Scalar, p> generateCouplings(unsigned N, Distribution d, Generator
   Eigen::Tensor<Scalar, p> J = initializeJ<Scalar, p>(N, std::make_index_sequence<p>());
 
   std::array<unsigned, p> is;
-  populateCouplings<Scalar, p, Distribution, Generator>(J, N, p, is, d, r);
+  populateCouplings<Scalar, p>(J, N, p, is, d, r, std::make_index_sequence<p>());
 
   return J;
 }
-- 
cgit v1.2.3-54-g00ecf